I love studies, here is one that makes total sense..

A new study presented at the American Sociological Association's annual meeting found that men are still paying for most dates.

Over 17,000 unmarried, heterosexual men and women were surveyed about their dating expenses. The research found that 84 percent of men and 58 percent of women reported that the guys paid for most dates, while 64 percent of men said they wish women would pick up the tab and 76 percent of them said they felt guilty admitting it.

I don't see any problem with her paying form time to time... come on!! haha