I feel the same way. It's one of the reasons why I'm so fond of reward mystery shopping opportunities when they come along. I much rather help people get recognized for doing the right things when they are doing them, and helping them move up rather than play a role in their downfall when they aren't. Feelings aside, they do seem to offer quite a bit of money for each bust, but I wonder how many times an auditor must pay door fees, and other expenses before having it pay off with a commission. Even though it is not a sales job, it would seem like you would have to have a sales person's mentality to be successful at this as you can not allow yourself to be easily discouraged, and must accept that not every lead generated will make you money (or as a former boss once told me, for every 'no' you get, you are one step closer to a 'yes').
Overall, I think I might be more comfortable sticking to jobs that I know will pay, and not necessarily result in someone losing their job over a cause that I don't necessarily feel passionate about in the first place.