This is actually a REALLY GOOD topic to touch on. Being from the D.C. area but going to school in Baltimore, you def notice a few things. This could either backfire or step your game way up.
Not saying this is for generally everyone, but when I go to a club in D.C...it's a bit tougher to get your game correct. Much harder to get those dances and those numbers so to speak. You have to be a bit more aggressive and assertive. Usually, the types of cats that really get the females they want roll a bit dough. Meaning, if you have a table with a big bottle of Ciroc, Goose, or something that costs over 400-500 bones, the girls will flock to you. That's just what I've seen...
Baltimore - it's a bit different. You see, most of the time if you buy a drink for a girl there, they will play you like a video game or just look at it as oh ok. Cool. That's it. If you really want to impress a girl there, lay back do your thing. They will come at you or just be yourself. Sometimes, if you are a really good dancer, they will get at you, too. That's just from my personal experience. Hell, even sometimes they'll buy you a drink themselves!!!
As you can see, buying a drink could either be bad or good depending on your situation, what club, what girl you are dealing with..etc. In any case, if you can tell a chick is generally interested you, you have a good convo, a dance or two or something and SHE DOES NOT have a boyfriend, by all means....do your thing. Peep what the Tipsy Bartender, Raychel, and Keziah have to say on the situation.