They probably get ads and displays in the retail stores. I think it'd be hard to launch a new phone brand without a retail presences even for Amazon.

I thought this was a good point until I realized the traffic Amazon has to it's home page and how many of it's devices are Top 5 sellers in major categories. Still, you could be right that they wanted even more than just Amazon alone could do for the phone.

Google has a pretty popular homepage too, but I bet having the phones available in stores led to more sales.

(Well, OK, and they were also really cheap or sometimes free with a new plan.)

They shouldn't cooperate with the carriers at all and fire some legal shots at the subsidy contracts. WP7,7.1,8 showed why cooperation is bad idea.

Bezos just don't have the money to compete with the big boys and should be looking at breaking the current model.

As a first time phone maker it was probably easiest to work closely with one carrier so that the design team could work closely with a single certification team. I know lots of companies make phones now, but it is still a big engineering problem.

That's the point where I put my wallet back up.