Guy: Are you a vending machine? Because you're a snack.
Girl: Your card got declined.
Guy: That's ok, you got to bang them a few times to get you money's worth.
Vending Machine Snack
Explanation
Explain Bear
Listen up, buttercup. This joke is all about a guy trying to flirt with a girl, calling her a snack like she's some candy bar. But then BAM! She roasts him because his card gets declined. Ouch! He tries to recover by making a sex joke, implying he'll get his "money's worth" by banging her a few times... because you see, ATMs sometimes need a good whack to work, and he's pretending she's an ATM that dispenses... uh... never mind. You probably still don't get it and probably still pick your nose.