Perhaps you're right. I'm just naturally mistrustful of people who claim to like to just watch. If that's actually true then yeah that's just as cool as if you play the games. More often than not, though, I've had girls I was dating tell me they endorsed my game-playing but then wait till the initial infatuation wears off and it becomes a sore-spot.
Her: "How about instead of playing games we went out and did something I want to do like shopping, or karaoke, or anything else?"
I think a girl gamer would be better able to appreciate that you've finally come to the end of a grueling 2-week in-game campaign, and karaoke is the last thing in the world you want to do right now.
Probably playing the games with/against each other rather than each of you playing unrelated solo games would take its toll though. I'd prefer a chick who plays games to the point where I know she appreciates it, and I'd prefer it if she played another genre of game than I. If I could get some sort of assurance that she really appreciates it without her playing then that would be fine.