I've been to japan 5 times. Its part of the "US" lowrider scene there. They see the latins dressing that way, so they do too. I even got a mag of bosozuko cars, and they were selling lowrider clothing.
But maybe there are street gangs. i saw a dude on myspace, he's a rapper and he was claiming Florencia 13, but flamed up, and saying Blood in some of his stuff..
There is clearly a language barrier, i found out first hand. But someone didnt get the message straight.