Take the blinders off pal, The ONLY reason I know about the gang affiliations was I wore my Celtics cap to my wife's school when I brought her something she needed and the resource officer asked me to remove my hat or leave the building. Asked why and officer said policy was because of gang affiliations being covertly advertised using athletic wear.
THAT's how I know has ZERO to do with racism and everything to do with a local government policy and I live in farm country where gangs supposedly don't exist.
Here's a Link from the NC Gang Investigators Associationon the subject.
www.ncgangcops.org/archives/Team%20Logos.pdf
And another from the NY Post
http://nypost.com/2012/08/26/no-good-comes-from-gang-inspired-sports-apparel/
So if your local team wins the playoffs and your kid is sent home because of wearing something associated with a sports team this is WHY.