Because if $2.99 turned a profit Amazon would be d

Because if $2.99 turned a profit Amazon would be doing it. I imagine even at $4.99 the company at best makes $1.

I presume content is either bought upfront or with a percentage split. They paid a million for Interstellar. We know for sure they didn't sell a million rentals on it.
If I recall someone said it was less than a 1,000. Not sure how accurate that was. If it's upfront then the company has to sell thousands of rentals before they make a single penny. I believe it was already proven years ago the company was loosing something like $3 on every rental redeemed from those ridiculous holiday promotions.

I think the model can work, but not for old content that other companies already have. People aren't rushing out to rent Robocop. Ultraflix just has to have better "quality" new releases at a competitive price. Or movies that can't be found elsewhere. I think they should team up with niche companies like SHOUT/ARROW.

I still think DAY 1 PPV movies is where the future is. Something like $50 to rent a movie the same day it's released in theaters. They just have to solve the copy protection problem.