Let's compare apples to apples.
Alaska: DigEplayer is the only IFE available
TED: You already get free tedvision and music programming
Do you think that might have something to do with lack of enthusiasm for shelling out $10?
I mean, how many people are so addicted to tv/video that they can't find something else to occupy themselves (I usually sleep myself) for a few hours on a flight.
Obviously, United doesn't have enough room on board to provide a player to everyone in coach (as a free rental would allow), and $10 looks like it was on the high end, so they are taking the logical step of tinkering the rental fee to make sure that all of the players they do have space for are rented. Maximizing revenue and all that. That is the purpose of a trial, no, to fiddle around with things and get it right? We can't all be as perfect and omniscient as some of the Prophets (hehheh) on this board.