In "The Fridge" why does Nicole try so hard at making Gumball into a winner? Because throughout her childhood and adolescence she has always been called a loser. So once you think about it, she just wants Gumball to not suffer the same thing she suffered from back then.
Why was Gumball so caring towards Kenneth in "The Microwave", even though he was a repulsive monster? Because he was an ugly baby! He knew exactly what it felt like to be ridiculed for being born odd-looking, and so he wanted to keep Kenneth from experiencing the same thing.
In "The Flower" during one of Gumball's tirades about Leslie he calls him a "Self Pollinator" he basically just called Leslie a jack off
In "The Phone", Mr. Small most definitely would have died horribly in a fiery blaze if Gumball hadn't been there with the fire extinguisher.
In "The Mystery", Bobert, who is supposed to be an emotionless robot, is shown laughing genuinely at Principal Brown's predicament. And then, towards the end of the episode, Miss Simian erases his memory, which is never brought up again. However, we witness later in "The Robot" that Bobert desires to feel real emotion, even though we've seen that he can at least laugh. So, is it possible that Bobert was able to feel emotions, and that by wiping his memory, Miss Simian erased them, too?.. Bobert basically was robbed of all capacity to feel, has been trying to regain it ever since, and no one seems to care.
In "The Mustache", Gumball and Darwin get rid of their black hairs they begin sprouting by removing all of their fur with tape. Sure, it doesn't sound so bad with Gumball, but Darwin is a fish, and he does the same thing.
"Dodj or Daar" from "The Game" is quite terrifying, if a player picks up a dodj card whatever is on the card happens in reality and continues to happen until the game is finished. One of the cards reads "All players must hold their breath until the end of the game". What would have happened if the card was picked before the Wattersons were close enough to the finish to win the game in one die roll...