Right, so they'll have to split it up into vans instead of semis, like a 5Mb/s plan versus a 1Gb/s plan. But you pay for access to x vans/second--and potentially y vans/month.
Netflix shouldn't be charged more on the basis that they gave people a reason to use their vans.
But it's based on the weight of your car, not whether or not you're spending money at establishments the toll road owner also owns or based on the toll road owner's financial relationship to your car's specific manufacture.