" At $10.00 or so each rental and a cost of $1k to 2k per unit they need many rentals to breakeven. "

I completely get your point and don't necessarily disagree with your big picture but consider what airlines have offered passengers for decades....zero revenues for the entertainment they provide.

Rentable units offer not only a revenue source with greater entertainment value but likely, even at $2K/per, cheaper than an embedded IFE system...not to mention less weight which translates into lower fuel costs, which is a big deal.

Just an alternative solution for what airlines have and continue to provide their passengers.