Why am I automaticaly assumed as a "Skinhead" while I was in Essex Cnty Lockup in NJ?!?!?

I am a 6'3, slim, German-American 42 year old man, born and raised in New Jersey, YES I AM an ex-con, I do NOT look like a "dangerous" man, look at my photo(circa 1987), I was always more the wisdom, nerdy looking guy.. I did however bulk up nicely during my last bid in 94 - 99 when I committed Armed Robbery, you know I am one of those guys whos cool, I like Heavy Metal, my hair is down past my shoulders, I have a few tattoos, I like to drink here and there. But for petes sakes, since getting out of jail, I have been a Computer Programmer!!! So I was locked up recently for 5 months on charges of DWI in Essex County Prison(Home of Newark and bunch of other crap areas), I am not from Essex, I am from all the ways down in Princeton NJ. Anyway, the jail was about 55% African American, 25% Hispanic and the rest being mostly Whites with a few Chinese.. So whenever I went out of my cell, I was called "skinhead", "peckerwood", "white boy" or something along those lines. I let them know quickly, that ive been in the can a few times and I can handle myself, I got up and said "OH EY BRO STFU AND GET OUT OF MY FACE WE COULD HANDLE IT IN THE YARD TOUGH GUY" they didn't bother me much. But what bothered me was that I had to be locked up beside the lowest, nastiest, dirtiest specimen from the wild back in the jungles. Boy if I had some more Skinheads in that prison we wouldve made it a real rough time for those boys.