Originally Posted by JamesM

those are called MGP2.
you can create same site with free scripts like smart cj and inxy scripts.

they scrape all major tube sites or use db provided by tubes so they can get traffic back.

these sites make money from ads and sending traffic to tubes.

mostly the owners of such sites create hundreds of same sites and set skimming too low so users just jump from one site to another before he can reach to the video.