Also, we do need a social stigma against cads. Cads are men who take advantage of women. Why is this good?
That's not an aspect of feminism. It's a justification that slutty women use for behavior they know is self-destructive. "I'm not a whore, I'm liberated." Bull-fucking-shit. There's nothing liberating about having some meathead alpha-male ram a flashlight into you while his drunken fraternity brothers cheer him on. Male sluts (they exist), players, and cads don't have that excuse and therefore, at least, have to admit that what they're doing is fucked up and embarrassing.
The only feminist argument for casual sex is that women should be socially permitted to have casual sex as much as men are. Fine. I'll go that far. I think the social stigmas should be equal rather than hypocritically lopsided as they are now.
I mostly go the other way on how to equalize these attitudes. I think that casual hookup sex is contemptible and destructive behavior, but that the man should be condemned as strongly as the woman. After all, he's as much at fault as she is.