“I participated in an in-home product trial study. A coffee machine company sent me one of the coffee makers along with about 200 coffee pods. I received $7 for completing 3 short surveys. Plus, after the study, the company said I could keep the coffee maker. So, I got like 4 mos of coffee for everyone in my household, a free coffee maker and $7!” - David W.
Most reviewed paid survey sites effectively promise not to share personally identifiable information or not to share it without your consent. It's an industry standard by which legitimate marketing research firms are bound. But many membership sites reviewed don't make either promise or do so only in a limited or wishy-washy way. Unauthorized go-betweens don't have to honor marketing research privacy standards.