In all my relationships I've never felt like I've had to treat her to everything she wants, and that whenever we go out it's written in the unofficial relationship-codex that I'm supposed to pay for it all. You ask her out on a date, it's your treat. She asks you out on a date, you will find out what kind of person she is if she asks you out and expects you to pay.
I'm 19, and I've had 4 girlfriends. I can't remember a single one I couldn't treat as a buddy. I don't want to be with girls who crave being constantly glued to my face in public places 24/7, but I don't want a girl who won't show me any affection, but rather play playstation and call me "dude" all day, either.
You need to find a balance. There's a time where you're supposed to be intimate, a time where you're the guy and she's the girl. But there's also time be friends, share things 50/50 and behave like best friends, cause that's what you're supposed to be. I could never be with a girl if I felt uncomfortable all the time and feel I have to use 70% of my brain capacity to adapt to however she wants me to be.
At my school (just finished), there used to be this couple who were constantly in each others faces with their tongues all over the place, practically dry-humping on the tables in the cafeteria. I do that as foreplay when I'm going to sleep with a girl, not anywhere.
Rule of thumb, though: Never become her bitch.