Can Anyone Explain Winit Competitions?

I've won a lot of smaller prizes, such as DVDs, Blu-rays, film merchandise, tickets and magazine subscriptions on Winit. They are genuine and you can enter the same competition daily. They are very quick to enter (unless they bring back video adverts). Prizes are meant to be delivered within 28 days, but sometimes it's a bit longer.

I believe they are genuine because someone on here once said that he/she had won a prize off one of those Winit sites once. However, that competition that he/she had won had apparently received around 10,000 entries which explains why it's so difficult to win.

I don't bother with Winit posts being posted on here as I much prefer to go to the sites themselves so that I can see more clearly what Winit comps are going.

I still find it very strange that each provider/sponsor has the same prizes which means I can enter about 4 times for the same prize. Does anyone know if there is a home page where they explain how the site works and who is actually giving the prizes.......what do they get from it?

I would be glad if there was a way I could filter these out. I know people say it is legit but thousands of people enter because you can every day. I run ad blockers on my browser and every time I click on a comp then click through and its winit I see that sad puppy who wants me to turn my ad blocker off. Annoying.