Why do people always say that people from west virginia are stupid hillbillies?

I was born and raised in west virginia and can tell with out a doubt is hardly different from other places. And how can I be a stupid hillbilly when I made exceptionally good grades in school? The worst grade I ever got was an 89% on my grade card in english. And I wasn't a nerd either I was an athlete and was constantly getting in trouble with teachers for cussing them and for getting in fights. And I've lived in pittsburgh and boston for about a year and a half hen I was little and my freshman year in high school moved to alabama but we didn't stay there for long. And ask for the who hillbilly thing, when I was 19 I went Berkeley california for 2 weeks to see my cousins and it was hardly different there then it is here except for all the communists.