However in a truly competitive commodity market (and surely bits moving from A to B are a perfect example of a commodity), "charge by cost" and "charge by value

However in a truly competitive commodity market (and surely bits moving from A to B are a perfect example of a commodity), "charge by cost" and "charge by value" should converge, and when they don't we should be alarmed. If ISP X is making 1% profit on regular bits and then decides to make 10% on premium bits, why couldn't ISP Y come along and undercut them? Because the market is being manipulated through monopolies on infrastructure and lobbying for special treatment.