I was reading this and I’m just going to throw this out there: my best worst pickup line, when I had a use for such things, was pretty consistently “Are you waiting for your girlfriend or are you going to buy me a drink?” But when in a hurry, I would also go with “So, are you going to ask me out or what?”
Note the passive-aggressiveness AND the aggressive-aggressiveness, because I’m particularly proud of those.
Did it work? Yes, yes it did. Which I think proves that if you are a girl who a guy has already been checking out, you can basically just make vowel sounds at him until he buys you dinner.