This dead horse has been beaten, dug up, and beaten back into dust many times over.
It's a simple matter of creating games for a target audience.
Yes, Tomb Raider was primarily targeted towards adolescent males (13-25), the main demographic that own video game systems and play action games. But you know what? Many girls have come to like Tomb Raider and have given it mass appeal because Lara Croft embodies the strong, adventurous, yet sensual female that defies the norm set by today's societies. She's a role model if you will.
At one point I suppose you could determine that some games were sexist (i.e. LSL, Duke) but now most developers take into account that a wider user base will be playing their games, and violence sells much better than sex nowadays.