1) Amazon is pricing this service based on their business statistics, including frequency, likelihood of increased purchases and total shipping costs. They are doing it because they have calculated it helps their bottom line.
2) You may order enough items to get to the point where your avoided shipping costs exceed $79, but if you think you didn't pay for it you are fooling yourself, and trying to offer up your self deception as a rational argument.
3) Amazon is not going to pay any more or less for the cost of shipping because you have given them $79.
4) Amazon is not a shipping service. You are citing them as as if they are the equivalent of UPS, or FedEX, or USPS; they're not.
How any is this is disruptive to shippers is something you will need to explain. You go right ahead and pay your $79 dollars to Amazon. As you have already said, you will buy more, the items will ship, and the shippers will make more money. So disruptive. So irrelevant to this thread.
Well, duh!
2) You may order enough items to get to the point where your avoided shipping costs exceed $79, but if you think you didn't pay for it you are fooling yourself, and trying to offer up your self deception as a rational argument.
I used it once. Then I canceled within the free trial period they were offering. But that doesn't mean it's not a clever idea.
3) Amazon is not going to pay any more or less for the cost of shipping because you have given them $79.
Duh, again.
4) Amazon is not a shipping service. You are citing them as as if they are the equivalent of UPS, or FedEX, or USPS; they're not.
No, they're a Luddite-annoying service.
And, BTW, although they sell plenty of physical goods, they're also making a lot of progress moving books out of the shipping world and into the world of pure information.