The moment when Hooper visits the Brody household with some wine as a souvenir. Martin, fed up with the whole shark problem, starts filling his pint with the wine despite Hooper's protests that he should let it breathe. (Note that Brody's glass still has some whiskey and ice in the bottom when he fills it. Imagine what that must taste like.) Then, he gives Ellen and Hooper the smallest amount imaginable.
To be fair, Hooper did actually hold up two fingers as a way to tell Brody to stop filling his glass. Clearly, neither of them wanted too much, anyway. Brody, on the other hand...
And it's the red wine, even though they're having fish. And, considering Hooper's wealth and pained reaction, it was probably a pretty good vintage.
Ellen: Martin hates boats. Martin hates water. Martin - Martin sits in his car when we go on the ferry to the mainland. I guess it's a childhood thing. It's a - there's a clinical name for it, isn't there?
When Quint sees the shark cage, he doubts its reliability, saying "you go in the cage. Cage goes in the water. Shark's in the water," then smiles and starts singing "farewell and adieu to you fair Spanish ladies! Farewell and adieu, you ladies of Spain!"
At one point, Quint crushes a beer cannote Which at the time were made from tin instead of aluminum, so crushing one barehanded was far more impressive in his hand, and Hooper responds by doing the same thing with a styrofoam cup.
The vandalization itself, with a spray-painted shark fin and a speech balloon coming from the beach bunny: "Help, shark!"
And the hint that these were particularly well-researched vandals, drawing the fin in correct proportion to the woman.
Everyone treats Hooper like he's a fresh out of college kid. Dude has gray in his beard.
Richard Dreyfuss was 27 when the film was released, which isn't beyond college age depending on what degree is being pursued, especially in the sciences. Most Ph.D students don't finish their degrees until their late-20s, and even that can be prolonged depending on the research. Also, compared to Shaw and Scheider, he was relatively young. It is true, however, that this was a case of casting not matching the script as the script was adjusted for Dreyfuss. And people can start to go grey in even their late teens.
Quint's treatment of Hooper, in particular, seems to have more to do with white collar vs. blue collar conflict than age. When Quint pejoratively refers to Hooper as a college boy, the implication is that Hooper has led a sheltered life, in contrast to the hard knocks that Quint has experienced.
Also when he describes the guys who are severely overloading their boat:
"You know those eight guys in the fantail launch out there? Well, none of them are gonna make it out of the harbor alive."
In that same scene, Brody is on the phone trying to get the situation under control. Outside, his deputy, Hendricks, is just standing there smoking. When Brody tries to get his attention, Hendricks cheerily waves at him.
The horrifying scene of Charlie barely escaping the shark ends on a fairly amusing note. He probably says the most logical thing anyone could say after experiencing such fright:
Charlie: Can we go home now?
During the scene with the tiger shark, we get this little gem from one of the fisherman:
Fisherman: Well what kind? What kind of shark?
Hooper: Tiger shark!
Fisherman: A what?
For the last line, it's not so much the quote itself but the tone in which he says it.
Also, as the journalist is trying to get the fishermen to pose for a picture, Quint can be seen cruising on by in the Orca snickering whilst tipping his hat slightly. Obviously he can tell that they've got the wrong shark!
When the shark makes it's first appearance while the trio are out on the Orca, Brody's reaction is to freak out, and Quint's is to prepare to harpoon it. Hooper's reaction is to excitedly grab his camera and start snapping photos, while demanding that Brody get closer to the shark in order to give it a reference point for size. Brody... is not pleased with this plan.
Hooper: I need to have something in the foreground to give it some scale!
Brody: Foreground my ass!
Hooper's reaction to being plunged into darkness during the night attack.
Hooper: He ate the lights.
Brody's reaction after Quint destroyed the radio.
Brody: THAT'S GREAT! THAT'S JUST GREAT! NOW WHERE THE HELL ARE WE HUH?! YOU'RE CERTIFIABLE, QUINT, YOU KNOW THAT?! YOU'RE CERTIFIABLE!
Quint: Yeah, yeah, yeah...
Hooper has to remind them, oh yeah, they have a rather large and angry shark they have to deal with....
Hooper: Oh boys.... Oh, boys... I think he's come back for his noon feeding.
In one scene, Brody is on Hooper's boat, drunkenly ranting about why he moved from New York to Amity. Hooper's barely listening:
Hooper: (mouth full) "Fascinating. Want a pretzel?"
If you listen carefully, you can hear little Sean angrily declaring, "Michael, I don't like you no more!" when the latter refuses to wait for him to catch up while they're playing at the beach.
When the first shark sighting on the Fourth of July is revealed to be a practical joke by a couple of kids, the two boys pop up to see the entire Amity coast guard pointing rifles at them, prompting one of them to give this hasty excuse:
Kid: (pointing) "He made me do it! He talked me into it..."
In a behind the scenes case, Steven Spielberg's friend George Lucas visited the set and was very impressed with Bruce the shark. As he stuck his head into the mouth for a closer look, Spielberg pranked him by hitting the button to close it...and as usual, the mechanics malfunctioned and it was quite a job to get Lucas unstuck.
Quint spots Hooper playing solitaire with cards and utters "Stop playing with yourself Hooper!"
Hooper gets fed up with the Mayor's refusal to believe the shark is still out there:
Hooper: I think you're going to ignore this problem until it swims up and bites you in the ASS!
Though it mostly depends on which one you get, the skippers are this at some points in the ride, especially when they playfully alter their spiel to poke fun at some of the guests.