One question: how can I trust all of this?

Not that I'm being skeptical or saying "it's all a scam", but man I can't put a finger into this. I just want some guidance here because I really want to join this thing so I can have some nice extra cash/thingies/whatever. Don't know if it's the right sub to ask but I need clarification on all of this.

I must say I tried PrizeRebel and Rewards1 a while ago (I had a Lockerz account in the past but now it's just plain dead and I didn't even knew about it), but I was both confused and reluctant at the same time. I don't know if you really should be putting personal information (not talking about credit card numbers and those things, but your age and localization). I must say once I started "profiling to be eligible to more surveys", I quickly gave up since it was basically asking for my zip code and how many things I had in my house and the shit. On both websites. This might seem pretty idiot but I can't help it (before anyone asks I'm not a child/teen without parental permissions, I just don't feel safe doing those surveys).

So as you guys do this practically everyday, please help me: how do you do those surveys and offers and everything? Any risks even if you know where you're treading? What about the information on profiling (asking for your address for example)? Do you really give your information on profiling and later give fake data on everything or what? What am I missing here?