poisoning p2p nets - does the RIAA pay for the copies?

so if some agency poisons a p2p file sharing system, e.g. to try to limit copyright theft,, presumably the use some sort of degraded version of the actual file (else it would be trivial to detect that they just have a completely incorrect check on the file, surely)

but if they use something that has even some of the original copyrighted material, it is a derived work

so do they pay the artists?

if not, aren't they just as bad (worse:)???