Because it is different from the "norm". When people haven't experienced many things or different types of people in their life, typically younger kids and children laugh or make fun of them. Once they realize there are many shapes sizes and varieties of people, and they realize they, themselves, are far from perfect, they begin to appreciate peoples' differences..
Because it's not them who are like that...so they think it's okay to say mean things or laugh about people who are different.
If it was them who were different, they wouldn't be laughing or making fun.
Because they were themselves never laughed at for being different. As soon as someone learns how that feels they usually stop doing it to other people.
because they have nothing better to do and they probably think it'll make them feel better about themselves by putting others down
Ya it just annoys me so much /:
Because the are immature.