Would it be horrible if overweight people wouldn't be shunned, shamed, mocked and made feel less worthy? Being obese isn't healthy (everyone knows this), it's always good to keep in mind and people should aim for healthy lifestyle in all ways. These changes are easier to do when you don't feel like an outcast, depressed or insecure. Overweight people going to gyms and exercise get laughed at. Go for a swim for example and hear the snickering from people for how you look, even when you are doing something considered healthy. In worst cases it's not just snickering but straight up people shouting nasty things at you. And I think it's well researched that media setting too high bars in the beauty standards can be harmful in many ways. Also the perception on people what is considered to be fit/healthy and unfit/unhealthy is sometimes really skewed.
They don't work out to be superheroes, they have superpowers. Not every hero in comics, games and movies uses physical strenght or agility to fight crime. And you said it yourself, they are not real. What sense does it make to shoot lasers from your eyes?