Dally thinks of himself as quite the charmer. He is handsome and he knows it, although he is a "Greaser" and none of the Soc's "girls" will date him. His approach with Cherry is forward and abrasive and Cherry rebuffs him, although it is clear she is attracted to him. Ponyboy is shy and withdrawn and is awkward around girls, especially ones he finds pretty. Pony would never be forward with a girl that was "out of his social class."
Cherry is attracted to Dally, but because he is abrasive and very forward (and experienced), she rebuffs his advances (and she also does this, of course, because they didn't date "Greasers"). The Soc's and the Greasers simply didn't date each other. The social divide was very clear. Cherry is a bit softer with Ponyboy because she knows he is very naive and innocent, in many ways.