More or less Redbox' strategy too, from what I can tell. Prices have been creeping up ever since the major competition (Blockbuster et al) dropped out of the market. And I suspect it's not because the costs to run machines has been increasing...
I imagine a great deal of it is the studios increasing their take. This has been a perennial problem for Spotify and other licensees of other media content. Netflix rolls their own now.
Really, it's hard to imagine a future for Redbox in ten years. Even the convenience of a vending machine movie store is nothing next to me not even getting off the couch.
With the prices at $2, which becomes $4 if I don't remember to return it on time... I often opt to pay the $5 to rent using a digital platform. Only time I pick up from Redbox is if I am at the store anyway.
