How do women get men to buy them drinks?

I go to bars just that I tend to be shy and not talk to people unless talked to. Seemed though I don't create much interest in people. I think I am quite attractive physically, just tend to sit in one place and talk to people I know or in the periphery. Why do some women have men buying their drinks for them?
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+1 y
I guess the question was motivated by my ego. I was a little jealous of a new girl in my social group and my guy friend kept buying her drinks but never bought me any. She also got bought a drink at another bar by a some random dude.
How do women get men to buy them drinks?
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