Ohh don't get me wrong Western media is as bad, if not possibly worse (albeit I've seen Japan be bit more openly racist at times, usually anytime these use the word Yankee), It is just interesting to see the stereotypes of another country.
Heck Kaijudo is an American Pseudoanime and it makes an overly big deal about how the main character is part Asian (something... no one cares about, and makes the reference stilted). He also, oddly enough, has multicolored hair (black with Red... and let me say GOOD LUCK if you try doing that in real life).
Heck Hetalia is nothing BUT stereotypes and I actually really like it (Since the stereotypes while funny, are meant to be endearing...). Then again it is probably because through all the stereotypes and poor jokes it honestly feels like the anime is advocating world togetherness and that the world is a great place to live in (Once again... something the MOVIE got wrong! ERRR!). So none of the jokes ever come off as mean spirited or honest jabs at the other countries.
But it is like Anime says the major reason why Americans fill that stereotype so often without reprieve is because Japan has a serious inferiority complex with the United States... I mean a HUGE ONE!
One Unique anime that features American Stereotypes is Prince of Tennis. Why?
Because it did the "American Team" plot twice. One time by honestly treating the American players with respect and showing them as highly skilled and equally qualified players (In fact, the team leader of the American team is essentially the reverse of the main character with his father being abusive). The Other time by having the American Players be a stereotypical "ha, Japan sucks!" team to the point where the anime itself makes fun of how dumb this is.