Number 2 here.

I don't see why people care about stuff like this, I see it as a win-win situation, it's a chance to find out what a person is really made of.

If she's hanging out with a guy and manages resist fucking around with him, you'll know the relationship means something to her. If she cheats on you, you'll know she's untrustworthy and you'll have a reason to get rid of her.