Not sure how these sites actually work - can you actually withdraw the money? Do you have to put in your bank details.
I need to sort some car breakdown cover. Quidco gives you £30 back, but if you go direct you can get £50 free fuel. If I get through quidco, I'm guessing you can't get the free fuel?
Quite likely you get both, yes. The cashback goes to any reseller, Quidco acts as that but passes it on. They charge £5 per year but take it from any earnings so if you don't use it you don't pay. I once got £120 cashback for car insurance and the insurance itself was £156, so cost me £36 for a year.