No, every single one of these is literally the opposite of how people actually act. No one mocks fat people in the gym, no one makes fun of fat people for ordering healthy food (wtf??), and smokers are ostracized way the hell more than overweight people. And in some circles so are problem drinkers.

And #3 somehow manages to miss the point despite it being right there. People who "eat as much _______ as they want and stay thin" do so because the amount "they want" is a reasonable amount of food. Whether they don't want to eat more than that because they're full or because they're dieting or they don't want to overdo it or whatever, the fact remains that the problem isn't "eating as much as you want," it's that "what they want" isn't way too much of it.

The only one of these that actually happens outside of extremely rare cases is #2. Fat people will draw negative reactions from a lot of people for showing a lot of skin when a skinny person typically wouldn't. But all the rest of these exist in some kind of fantasy world that's up there with the stuff that ends up in /r/thatHappened.