The other day, I was participating in a research study. The point of this study is to find out which moisturizers work best. We study participants spend a certain amount of time getting moisturizers and getting tested, then we get paid. One of the other participants suddenly gasped "I just figured it out - we're not even getting minimum wage for this!".
I winced, because I knew what was coming. Sure enough, one of the employees (a very no-nonsense lady) scowled and said "This isn't a job. You chose to take part of your own free will, and the document you signed at the beginning makes that very clear." The participant made things worse, saying "Well, yes, I know, but still - minimum wage is -" "If you're dissatisfied, you're more than welcome to take it up with a lawyer." Participant immediately started to backtrack, saying hastily that she wasn't dissatisfied, nosirree!