[Dunedan]

> My biggest problem with this is that from what I can tell, the only way to know how much you're going to be automatically charged (as well as what items the tech thinks you're purchasing), is to go to a kiosk in the store and get a receipt.

You only need to use the kiosk once per credit card (to enter your e-mail address). From the page:

> If shoppers need a receipt, they can visit a kiosk in the store and enter their email address. A receipt will be emailed to them for this trip. If they use the same credit card to enter this or any other Just Walk Out-enabled store in the future, a receipt will be emailed to them automatically.