Oh, heads up, you're in for a treat. Amazon will try to tack on a Prime subscription on every order you try to make from now on. They do this with a permanent full-page interstitial (not a pop-up) for ex-Prime users before the order confirmation page whose big green 'continue' button automatically one-click charges your account for a full year of Prime. You have to read down and click the tiny 'no, I don't want these benefits' blue text link in 8px font size to file your order without Prime.

I no longer shop from Amazon. The more we accept these kind of indignities, the more they will be forced on us. Let them starve, that's the most powerful message one can send.

Edit / More data points:

- One more trick up their sleeve: they will default to two-day paid shipping even when you have free shipping available, just so that you'll feel the pain (i.e. the 'worth') of Prime every time you have to pay attention in the last page, and check the right 'free shipping' radio box for every shipment in your order.

- For me, the last thing that broke the camel's back was that they were specifically sending shipments to arrive on the last day of the shipment window. As a real example, I ordered a display on Jan 7 to arrive between Jan 14 and Jan 18. They shipped it Jan 17. This is what made me notice this, and it made me look at my past orders. Turns out, they have been doing this consistently, for a while.

The purpose of a shipping window is to allow for some slack in the case shipment gets delayed, it is for shipment. If they shipped it a few days before the window, that would be fine. If they shipped it right at the beginning of the window, that would still (arguably) be fine. If you ship in a way that is aiming for as late as possible delivery, that's pretty obvious what you're trying to do.

If you're not a Prime customer, your orders might arrive as late as they can make it. They are likely doing this on purpose.