Around here a couple of equine rectums ( I may have to start using that...good one) got it out for the repeater owner and would just do to pester folks at various times. They had enough sense to not stay on for long periods. We still found them and turned them into the FCC. It took a while for anything to be done, but the fines were steep and they lost their ham gear.
Repeaters are not the best thing ever, but they do have their place. For example, I have been able to talk with BWRR on a repeater between us using one. We live a good piece apart (I'm guessing 100 miles or better) and there is no way we could make contact on 2M without it, barring SSB. OTOH folks rely on them way to much and most will be lost if they all go down.