To me, this is a sticky subject. While I agree, dickheads who intentionally fuck things up should be punished, the punishment should fit the crime. Like for instance, leaving a small tag just to say "so-and-so was here" is one thing. Nothing wrong with it, everybody wants to leave their mark on the world. Spraying up a good spot, whether it's a catchout, a place to sleep or a choice dumpster, is wrong. It makes things harder for the next guy/gal. By all means, assholes like that should suffer but again, the punishment should fit. Curbstomping is a little much for that in my opinion. However, think of the poetry in roughing them up, taking all their stuff, and spray painting them.
Defecating someplace inappropriate? Rough them up a little, tie them up and dump a bucket load of shit/urine on them.
Being a general fuckhead and/or fucking up a squat? In this day of Email and digital cameras, it wouldn't be hard to get the guilty party's name and picture out to other squats/squatters. Let them know that the guy/gal is a fuckhead, if you let them in they'll probably end up blowing up your spot.
Rape on the other hand, be it by force or by intoxication should always be dealt with forcibly. By all means, curbstomp them, take all of their stuff, leave them naked in a gutter. Actually, that's not good enough. Tattoo them. Brand them for life as the scumbag they are. Someplace nice and visible, like their face.