re: Has anyone here ever been a paid secret shopper?

I do occasionally. Like others have said, you usually get reimbursed for the cost of the activity (dining or hotel stay), but some will give you an extra cash payment (like working out at a gym, you get the cost of a day pass plus a little extra). There are other things like placing a call to a retirement home and asking about their services and rating their service and such, but nothing that pays out significant cash that I've seen. I'll do a restaurant every now and then. It generally ranges from $25 reimbursement or a sandwich shop up to $150 for a steakhouse. I did a gym once just to go workout somewhere different for free.