I really don't' give a **** about stereotypes because it refers to a group. When people are stereotyping it's obviously not true, like for example, all Americans being fat, lazy, and stupid.
In my opinion being prejudice is much more serious/annoying because it's only referring to YOU, not a whole country or large group.
"Haha, they're all geeks because they wear glasses" Seems to be more lesser than "Brooze IS a geek because HE wears glasses".
Also with prejudice you're only defending yourself and your reputation, stereotyping seems that you've got a whole crowd to back you up.