>I don't really get why I should not be allowed to make fun of stereotypes of other "races".
By saying this I presume that you are ethnically caucasian. You are also male. Your stereotype, then, is "default." Had you a race or gender other than "default" you might have a better understanding of it.
I grew up white in a predominantly hispanic and native american region of New Mexico. There were restaurants I couldn't eat at, there were stores that wouldn't sell things to me (as in, you ask for help and they say "we're not going to help you, this place isn't for your kind"). I used to think that gave me a unique "white" perspective on racism. And while it certainly gives me an insight that a lot of white people lack, it doesn't go nearly far enough.
I mixed a truly, spectacularly large talent show a couple years back (think X Factor or Pop Idol or The Voice Of Holland - it was that big). We had people on that show that had experienced hardship - oh, my mother died. Oh, momma was on Welfare. Oh, I struggled with alcohol abuse. Touching stuff, nothing untoward.
Six months later I mixed a couple episodes of Sunday Best (It's not on my IMDb). For two solid days the 6-person sound crew were the only non-black people in West Angeles Church - no small feat. And we did the exact same interviews as you ever do. The level of hardship, on the other hand, was off the fucking hook - "God took my eyesight but I still believe." "My mother was shot last month but I believe." "I'm homeless but I believe."
It was really striking to me how the level of shit the African American community took as baseline was so much more impoverished and strife-ridden than what the White American community took. There are serious problems with affirmative action and saying "some are more equal than others" but it really is a pain in the ass being a minority on so many levels.
I don't think you understand that. And when you poke fun at other racial stereotypes, you remind people of that fact. It's a boundary, it really is. And since you've never been over that particular border, you aren't aware of the fence that keeps things civil.