It gets offset by having multiple videos on the screen that give you 5 credits for watching a 30 second video. My personal favorite is the Doritos one where the valet takes the guy's car and picks up a giant Mexican banana.
Also, today, I got 22 credits from Home Depot for dragging 3 tools onto 3 different screens.
Usually I just have the 7 carousel vids on in the background with the other 5 credit/show vids and the 2-3 credits I receive from a walled video...all at the same time.
My only complaint is that it slows down my porn downloads for a while. Give and take, I guess.