Earlier quoted context omitted.
Amazon doesn't have unit cost for egress. They charge you for the stuff you put through their pipe, while paying their transit providers only for the size of the pipe (or more often, not paying them anything since they just peer directly with them at an exchange point). Amazon uses $/gb as a price gouging mechanism and also a QoS constraint. Every bit you send through their pipe is basically printing money for them,…
Honest question, how is this different than a toll road? An entity creates a road network with a certain size (lanes, capacity/hour, literal traffic) and pays for it by charging individual cars put through the road.
First a lot of these roads are 'free' and yet you're still being charged for it. If two large networks come to an agreement then they connect the two networks (ie build that road), but no money changes hands.
Second if there is a paid peering agreement in place (ie say AWS had a cost to push your data out), that still wouldn't be billed to them in the way they're charging you. Instead they'd be paying for the rate of traffic at something like the 95th percentile of the max. This means that you could download a petabyte of data from them when the pipe isn't busy and cost them nothing, or you could download a gigabyte when it's busy and push up the costs.