Yes, bluegrass works very well. Mexicans in particular hate it.
Classical, new age, and soft jazz will all deter thugs. Rap and heavy metal will attract them. Decent people are attracted by music that thugs hate and repelled by music thugs like. A businessman can select his clientele by the music he plays.
I tend to prefer it when businesses play no music at all, however.
Bar owners have known this since there were jukeboxes.
Jukeboxes? Am I really that old?