You answered your own question.... people start beef when they don't pick up girls.
I hear you man, but man back in my single days I stayed out Monday -Sunday and if I didn't pull no a$$ that night whatever....I'd go even harder the next to get some....never violence..even though I knew I could go there if I needed to and most cats weren't.
It's like the violent bar/club types are there for that only...violence. zero intentions to get with the females. Just waiting to hate basically on a GUY. lol...crazy.