Because one per day is completely unsustainable and they only need to last longer than MoviePass burns VC money and fails?
Giving theaters more lee-way on how to pay for the movies they are licensing will allow for much more competitive opportunities and differentiation between theaters.
Are we sure about that, though? I assume these people are not complete idiots. I assume they had a team of economists and business analysts crunch the numbers on this beforehand. The cost of a ticket seems trivial to the added benefit of having your theater full of hungry, thirsty patrons at what would otherwise be off-peak times. I think this is going to be a massive boon to the industry, and may even see theaters evolve into more like "family fun centers" and general hangout locations.