[schleyfox]

Amazon Prime isn't free shipping (as far as I know >$25 standard shipping is still a thing). It's a flat rate for unlimited 2 day shipping. Two day shipping is expensive, but the combination of an annual fee and the increased likelihood of purchases for subscribers is good for Amazon's bottom line. Subscribers get faster shipping and pay less as long as they order more than four or five things a year. It seems like a pretty decent win for both consumers and Amazon. I imagine Amazon's brick and mortar competitors are somewhat less amused.

[SoftwareMaven]

I order a LOT more through Amazon because of Prime than I would otherwise. Knowing my buy-to-hold timeframe is only a couple of days and Amazon's price will be significantly better than other places means Amazon usually gets my first look on almost everything.

I have no idea if I am a profitable customer or not, though. My guess is that the profitable customers with Prime purchase very little or a lot. I don't think I fall in either of those categories (though I might before Christmas is over :).