Very easy. My first and only pay-purchase at Amazon was by accident while I was trying to get a sample using my computer. Via the website at least, they go straight to "bought", no confirm-you-want-this screen, so I didn't notice until I started reading and realized the sample seemed unusually long.
I decided not to return that book because it was
- something I was more-or-less interested in at the time,
- wasn't available via the local libraries,
- didn't cost that much and was then cheaper than at the other stores,
- I'd already read 2 of the author's other works as free promos and a third via the library,
and most importantly, I'd lose out on after the CC exchange back to Canadian dollars.
But I've now padded my account with gift certificates so that if it happens again, at least I can refund it without any extra cost due to the currency conversion.
I wish they (and all the other majors) had the option of a shopping cart function that would group all your prospective purchases and calculate taxes and such.
That's about the only redeeming feature of the Sony store, which they make you use their hideous Reader Library software to get their books via.