In priority shipping, only one side pays the fee. If the post office or UPS said "oh you want it there faster, pay X" to both sender and receiver, and both were required to pay for it to be faster, then it would be the same.
So when I pay for gigabit internet, and netflix pays their "streaming priority" charge, I get netflix content at gigabit speed.
But when I pay for gigabit internet, and some random startup doesn't pay the ISPs "streaming priority" charge, I get them at some rate limited amount less than what I pay for (gigabit).
That is the problem. The consumer gets screwed, startups get screwed, and the ISPs profit from both consumer and businesses.
In reality the cost is really distributed. The sender hands over the money to the shipping company, but that money comes from the receiver.
And the infrastructure is supported by the community at large.