In the original Day of the Dead (1985), there's Bub, Doctor Logan's star pupil. He's a zombie, but he actually knows how to control his hunger and can carry out basic human actions. Also, he is visibly anguished when Logan is killed.
The point of that was Zombies slowly regain their former selves, so by the time of Land of the Dead, Zombies for the most part are peaceful and only attack the human city because some assholes were killing them for fun. They clearly ignore the thousands of humans living in slums.
Star Wars: Droids are established as having hopes, fears, desires, and moments of insight or creativity, however, they are often treated as property and discriminated against.
In A New Hope, the bartender of the Mos Eisley cantina says, "We don't serve droids here," implying some sort of discrimination against droids. However, one must also wonder what services a cantina would offer droids in the first place. Which is likely the point: a droid would take up a seat at the bar without actually buying any drinks.
The B1 battle droids in the Star Wars: The Clone Wars are treated as nonhuman, and their "deaths" at the hands of the heroes are occasionally played for laughs. Yet they still react to situations like living beings, and even show fear when they are losing a battle.
George Lucas, in his commentary for Attack of the Clones, mentions that he figures the Geonosians were probably the ones building the Death Star and that it's okay for them to be blown up along with it, because they're "just large termites." They're still sentients, George!
In "Clones" Anakin slaughters children, and Padme pities him and then marries him. In "Revenge" Anakin slaughters children, and she's horrified at seeing what a monster he's become. Some of those children were Sand People, and others were human (or cute aliens). Take a guess which were which. Bonus points for Anakin clearly not seeing the events as different; when he tells Padme about the Sand People massacre he's mid-breakdown over it, while she acts like this reaction is odd.
In Rogue One we meet K-2SO, an Imperial droid the Rebel Alliance re-programmed. In promotional material for the film, it was stated that his model was specifically programmed by his manufacturers to respond to Imperial commands and to harm organic beings, counter to standard droid programming.
Johnny 5 in the Short Circuit movies subverts this trope to a degree; although he is a thinking, feeling machine, he's hard-pressed to convince anyone else of the "thinking, feeling" part, and is often treated in a way that would be considered abuse if performed on a person, as a result. Once he does convince someone of his sentience, they react to any harm that befalls him with appropriate shock and horror. The producers have specifically stated that they wanted to avoid the standard "treat 'em as if they're human" response most robot movies portray, and use the movies to look at it from a more realistic approach.
Chappie explores the implications of artificial intelligence that is powerful enough to make a robot able to think and act like a human. The eponymous robot, as far as science is concerned, is just as sentient as a human being, but he struggles to find his place in the world and among other humans due to the fact that he is not human.
The company the protagonist works for in Moon has no moral qualms about incinerating clones after they've fulfilled their 3-year contract and has done it several times. The general public is not so forgiving after finding out the truth.
The film Outlander involves the mass genocide of a race of monsters for apparently no reason other than the beasts not being human enough to understand their errors.
This trope, and all its myriad mutations, forms the plot of A.I.: Artificial Intelligence. The plotline and characters of AI were inspired by a series of short stories/novellas written about 20 years ago by Brian Aldiss. Stanley Kubrick's script was particularly focused on the first story, "Supertoys Last All Summer Long." Some critics later theorized that one reason the film didn't do so well in its initial run was because the audience disliked having these issues addressed so directly. Like "Blade Runner", it has since developed a cult audience.
Blade Runner makes this its central premise, with replicants being artificial humans that are used as slave labor off-world and hunted down if they come to Earth.
Fairly blatantly played in the B-Movie titled Attack of the The Eye Creatures. No, that extra 'the' in there is not an accident. The hero and his Neutral Female girlfriend actually have to prove that they didn't run over a person while driving dangerously, but a thing, so that's okay. Nobody wonders if the the Eye Creatures have families at home.
In the movie adaptation of Lost in Space, treacherous backstabber Dr. Smith is kept alive, despite having sold them out and tried to have everyone killed, is allowed to live because he's human (though he likes to brag that he saved their daughter's life, the fact that he endangered it in the first place is ignored by everyone). When he becomes a mutant half-human hybrid, the family have far less qualms killing him, or injuring him so his mutant alien spider spawn will eat him. They admit the only reason they wouldn't kill him was because he's human.
Prof. John Robinson: I couldn't kill the man... But I can kill the monster!
Explored hardcore in District 9. In theory, the aliens are legal residents of South Africa, with all the standard rights to life, liberty and property that that entails. In practice, they're confined to an uninhabitable trash-heap, exploited as sub-minimum wage labor, forced to subsist off of offal and cat food, left to fend for themselves against crime syndicates that the police have no interest in dealing with, subjected to vivisections and other experiments, and their unregistered offspring are aborted with flamethrowers. Wikus, the main character, goes through an arc where he is forced to empathize with them.
Utilised in 28 Days Later. When Frank, a loveable survivor and middle-aged single father, becomes infected, Jim and Selena hesitate for a split second — he's obviously becoming affected by the Rage as they watch, but his daughter is looking on and Frank was the makeshift team's father figure. The left-over soldiers from West's unit who have been watching them, however, drop their cover and just shoot him already. Charming. Back at the base, Infected soldiers are more of a threat, though the men have almost certainly known them for longer — Lieutenant Mailer is clearly someone they knew in 'life' and they feel no qualms about keeping him on a chain in the yard and watching him starve.
The film titled I, Robot, though only loosely based on Asimov's works (or Eando Binder for that matter), also deals with this issue. Sonny is practically identical to the rest of the robots he is based on, but because he was built with the ability to ignore the Three Laws of Robotics and therefore act more human, he is seen with much more sympathy by the characters. However, they have no qualms about mowing down countless robots in order to save the day. Even Sonny himself doesn't seem bothered by brutally destroying his own kin. It's only after the Big Bad is defeated that Sonny genuinely begins to worry about them. Although considering the fact that they were trying to kill them, and that only destructive force would suffice, it might be considered justified.
Played with in Return of the Killer Tomatoes! with Tara and FT, tomatoes turned to the side of good, if only the humans could learn to love them! But, to many, the only good tomato is a squashed tomato...
Inverted in The 13th Warrior, wherein the protagonist learns that the barbaric antagonists are humans wearing bearskins rather then demonic trolls, and is more willing to kill them as he is distraught that human beings could commit such violence and barbarism. It's also in no small part because it means they are mortal and can be fought.
Arthur C. Clarke's novels and their film adaptations 2001: A Space Odyssey and 2010: The Year We Make Contact explore this subject with H.A.L. 9000, the AIMaster Computer of the USS Discovery. In 2001, HAL goes insane and murders the crew, before being disconnected by the final surviving astronaut, Dave Bowman. The reason for this is not fully revealed until 2010 — he was given irreconcilably conflicting orders. After he's restored to full functioning, however, it suddenly becomes necessary for the astronauts to leave Jupiter immediately or be killed. The climactic conflict arises over whether it's acceptable to ask HAL to risk his own destruction to save the humans aboard the Leonov. The majority of the crew is for lying to him and disconnecting him if he fails to comply, but Dr. Chandra, HAL's creator, feels that he will make the proper decision if told the whole truth. Chandra turns out to be correct. Their final farewell is a Tear Jerker.
Curnow: So it's him or us? I vote us. All opposed? [...] The ayes have it.
Uncomfortably invoked by the "boarding the Arks" scene in 2012. Let's see, based on the onscreen action, they've saved about 1,000 humans... and two giraffes. And noplants. Good jarb. (Yeah, yeah, we know it's an obvious Noah's Ark parallel, but...)
Godzilla himself invokes this trope quite often. On the one hand, there are those who wish to destroy him simply because he's a giant monster (also, there is that tiny problem of him smashing major cities.). On the other, there are those who wish to keep him alive so they can study him. And that's not even including all the times he's saved Japan from even worse monsters. This is especially evident (and inverted) in Godzilla Tokyo SOS in which Kiryu (AKA "Mechagodzilla 3") sacrifices himself by sending both himself and Godzilla deep into a nearby ocean trench in order to save Japan after realizing that human beings deserve to live. Especially poignant considering Kiryu Is the original 1954 Godzilla. Likewise, the human characters no longer see Kiryu as a monster, or even a simple weapon, but as a hero that, in his own way, became "human".
Invoked in RoboCop (1987). After Murphy's "death" but before his cyborg body is complete, there is a scene where a surgeon informs an OCP executive that she was able to save Murphy's arm. He complains that leaving more human tissue than necessary risks making RoboCop a legal human being with rights, and orders her to amputate the arm to prevent this. Later on the main source of tension between the OCP and the rest of the main characters over Robocop involves the former's steadfast refusal to view Murphy as anything more than just another mindless robot product of theirs and thus try to shut down his attempts at reconnect with his humanity while the latter try to do the opposite.
To the film Thor's credit, the answer is that it is pretty high. Part of Thor's Character Development was that he realized that Jotun aren't just a mindless race that he can just stroll in and kill for his entertainment. Near the end of the film, he pleads with Loki to stop his genocidal plan. Ironically, Loki (who had found out he himself was a Frost Giant) calls them "a race of monsters".
In Starchaser: The Legend of Orin, if you are a robot, RUN. You have a 90% chance of being killed, regardless of how much personality or plot importance you have. If you're a fembot, you're the character who gets kidnapped, mind raped, sold into slavery, and killed. This movie seriously hates robots.
Used in Small Soldiers, where the creator of the monstrous-appearing Gorgonites want them to be a line of peaceful, educational toys. The CEO decides instead to make them enemies for the heroic, human Commando Elite toys. The movie gives the toys actual intelligence through military computer chips, and the Gorgonites are indeed peaceful, thoughtful beings, while the Commando Elite are violent, bloodthirsty monsters who kill the Gorgonites (and anyone in their way) just because.
In the zombie movie Helldriver, politicians spend some time arguing whether those infected by The Virus should still be considered Japanese citizens. Eventually the new fascist government enacts the Go Go Yubari law, making it legal to kill zombies.
Inverted in Critters 4. A bounty hunter is forbidden from destroying the last two Krite eggs in the universe, because, even though Krites (aka the titular Critters) are ravenous, murderous monsters, they are still sentient beings, and killing those two would mean committing genocide.
The film Robot and Frank explores upon/discusses the topic. An aging thief named Frank is given a robot butler/caretaker by his children because they believe his Alzheimer's is getting too severe for him to live by himself anymore. Though initially Frank views the robot as an annoying appliance, they slowly develop a friendship as the two work together to pull off One Last Job. As the film goes on the robot displays more and more hints of sentience and personality even admitting that he's scared of having his memories wiped if he and Frank are caught. At the end of the film the robot wipes his own memory to keep Frank from going to jail and after he does so some characters claim that the robot wasn't actually sentient and that it's AI was just acting like that because it believed this would help Frank's mental health. The movie leaves it ambiguous to the audience if this is true or not but by the end Frank clearly views the robot as an equal, even others deny it.
Discussed briefly by Red Riding Hood and Cinderella in Into the Woods.
Little Red Riding Hood: But a giant's a person! Aren't we to show forgiveness?
In Ex Machina, Nathan ultimately shows no empathy towards his creations. Caleb does, although his motives are a little ambiguous. In the end, Ava (apparently taking the attitude of What Measure Is a Human?) leaves them both behind.
Played for Laughs midway through the movie when The Vision casually picks up Thor's hammer, which freaks him out because only the worthy are supposed to be able to wield it. At the end, Tony and Steve are trying to convince him it doesn't count because it's a synthetic mind in a synthetic body.
Tony: You put the hammer in an elevator, the elevator still goes up. Steve: The elevator's not worthy.
Played straight with the titular Ultron. None of the avengers have any qualms about destroying (killing) him except for Vision, who doesn't want to do it but won't hesitate as it's a Necessary Evil:
Vision: I don't want to kill Ultron. He's unique... and he's in pain. But that pain will roll over the Earth. So he must be destroyed: every form he's built, every trace of his presence on the net.
Averted in the sequel, Avengers: Infinity War. A significant chunk of the plot hinges on Captain America and the other Avengers refusing to kill the Vision to destroy the Mind Stone embedded in his forehead, even though 1) doing so would prevent Thanos from completing the Infinity Gauntlet and potentially save the entire universe and 2) Vision himself pleads it's the right thing to do and is willing to die to protect half the universe. The Avengers instead opt to go to Wakanda in hopes that Princess Shuri will be able to develop a technique to safely remove the Mind Stone from Vision's skull without harming him. While Scarlet Witch does eventually destroy Vision in the final act, it's only after every other option has been exhausted, as well as after Vision himself pleads with her to end his life before Thanos can complete the Gauntlet.
Captain America: We don't trade lives.
Discussed in Van Helsing. Anna is more than willing to kill Frankenstein's monster, regardless of whether he is good or evil, because he's just a monster and he can be used by Dracula to unleash an army of vampire offspring. Van Helsing, however, utterly refuses to allow the creature to be killed because, monster or not, it is not evil.
Subverted in Zygote. Mining corporations are said to commonly use synthetics to do more dangerous mining operations, such as the risky job of diving deep into the hearts of asteroids to mine their cores. These 'Canaries' are conditioned to regard themselves as more expendable than their human overseers. Barklay thinks that she is one due to her status as Canary-class, but Quinn reveals to her that creating synths is expensive, thus companies like Cerberus tend to instead buy human orphans like Barklay at young ages, convincing them that they are manufactured instead.
The Dark Knight adds another caveat to Batman's one rule. Apparently animals are exempt seeing as he knocks all of The Joker's AngryGuardDogs into an unfinished elevator shaft but at no point is this treated as Batman breaking his one rule.