This is where it can all go downhill quickly.  In the pressure to make as many pennies out of a nickel, a lot of research corporations will not just sell your answers but the data associated with it.  Details that you provide when taking paid surveys such as your name, address, age range can all be attached together quickly to fulfill a lot of larger companies' requests for information (RFI).
It’s easy to earn cash for surveys. How much you get paid completely depends on how many paid surveys you attempt and complete. Each online survey has a different payout, with some offering as much as $50. Most will pay less, but also take less time. Expect to earn about 40 to 200 SB points per survey (100 SB = $1), with occasional opportunities with much higher earning potential.