If copyright law said that the price a piece of content is available for is the highest amount any provider in a region is willing to pay then you're setting up for a monopoly, as Netflix or Amazon Prime with their near infinite content budgets set the price of everything they like higher than any new competitor can afford to pay.
Sorry, I don't think I expressed that well, I intended to say it was akin to a "most favoured nation" situation; if Netflix get a lower price per person, then you have to offer that price to others.
I can't see how Amazon and Netflix could push prices up without unlawful collusion? But if they did push prices up for all media how would they sell their service?
It's not unheard of for major players to have contracts that say 'if you're offering this to another company for less per unit than you are to us then you agree to reduce our price accordingly', the idea is just to make that lowest price universal so that.
I sell license for prints of my painting to Acme for £5 then ABC can print the same painting and pay me £5. As creator I can choose not to sell the work for £5, but that's no different to now; what I wouldn't be able to do is restrict who - in the wholesale market - could buy the work for that price.
