If a script deleted things on someone's computer because it didn't like what the user did I don't think anyone would download it a second time, they'd just remove the whole thing and get word out for nobody else to use it. Just because someone edits a script, doesn't mean they're ripping it. Anything which tries to use integrity checks or put pointless variable checks is hindering that ability, and I would guess that there's a whole lot of people who wouldn't appreciate that.
The whole *scourge of ripping* thing is entirely over-exaggerated. If you were able to get an honest answer from people you'd find that probably about 1% of those who go on about ripping have actually had something ripped. Anyway, if you're really worried about ripping there's one simple thing you can do that will stop you from ever being ripped: Simply state in your script that people are free to re-use whatever code they want. Maybe some will give you credit, most probably won't, but you'll never be ripped again, that's for sure.
