Those mystery shopper ads are some of the worst and that is certainly a scam. Hopefully some others will chime in because there are some channels for reporting the crooks. At least you weren't one of the ones who believed you would get something for nothing, or next to nothing.
If you have an interest in "real" mystery shopping why don't you pull up a chair and stick around for a while. We are a mixed bag, but most of us know a thing or two about legitimate mystery shopping, well at least a thing maybe not two
Equal rights for others does not mean fewer rights for you. It's not pie.
"I prefer someone who burns the flag and then wraps themselves up in the Constitution over someone who burns the Constitution and then wraps themselves up in the flag." -Molly Ivins
Never try to teach a pig to sing. It's a waste of your time and it really annoys the pig.