I was at lunch at the Speckled Butterbean, across from Brownwood, before it closed, and about 25 grungy looking bikers came in to eat. They wore "colors" to indicate that they were affiliated, and some wore patches that indicated they were "1 percenters." That is gang code for not caring about the conventions of regular society. Many were wearing knives.
At the time I was getting around with a walker. As I approached the door to leave, one of them came over and held the door for me and gave me a pleasant smile. You can't judge entirely on appearance.
Of course in a different situation they were probably capable of very nasty behavior.