Oh, and my thoughts on the badass persona aren't specific to chicano clicas - "clubs" as they were called then, sprouted up around various different shared interests in the post WW2 era: motorcycles, cars, military affiliation, and yes, various forms of neighborhood groups. Exclusivity and an "us vs. the world" attitude were a common insulator for many of these groups, not just street clubs.
The idea that mainstreamer musicians (or mainstream dreamers) would not want to be associated with societal outsiders or punks isn't too surprising - non-conformists were much less accepted then than they are now. But look at the fringe groups, the ones without an ideal music "career" (right now, I'm imagining the groups featured on the covers of the Teenage Shutdown series). They were definitely working that outsider vibe, 'I don't care' attitude.