So, what's so bad about the Amazon App Store? Well, I personally don't mind that it runs continuously in the background as a kind of license server, though some people complain that it's hard on battery life (while others disagree)... my real beef with the Amazon App Store is its always active one-click: no password, app ordering, always available. The only way I have found to deactivate one-click app ordering is to uninstall the store, which deactivates ALL the apps that use it for license checking, which includes about 18 of the 20 apps I have tested.
You can say that Amazon's customer service is excellent and that they will refund any accidental purchases, you can say that they notify you of every app purchase immediately in e-mail; free and paid app purchase notifications look identical in every way until you click on each individual transaction to open it, and it is the same in Amazon's account review. This feels like a return to the old Record/DVD Club days where you get a bunch of cool stuff you want, very conveniently, for a reasonably good deal, but then have to fight to turn the thing off and eventually get charged for something you don't want, especially if you ever hand your tablet over to an elementary school aged child to play with unsupervised for any length of time.
After getting sucked in on the Free Apps, I finally purchased a couple of paid apps and was fairly shocked that, unlike the iPad, I didn't have to put in any kind of password. It's much less the 2x0.99 that bothers me than all the time and effort spent setting up two tablets, just to find out later that if I don't want to leave my credit card fully exposed for app purchases, I'll lose use of all the apps I have installed from their store. So, suck the customer in and after they have invested maybe 20 hours into your ecosystem, finally give them a clue that there's no way to turn off purchases, the parental controls options only apply to in-app purchases, not to app purchases themselves — and if your kids are smart enough to get into the master app listing, they can always launch the app store.
Response from Amazon Customer Service:
It was a pleasure to speak with you today! I know your time is valuable and I appreciate you spending some of it with Amazon Appstore support. Thanks for suggesting we add parental control for App purchases to the Amazon Appstore for Android. Customer feedback like yours really helps us continue to improve our products and provide better service to our customers. I've passed your suggestion to the Appstore team for consideration as we make future improvements. Thanks for taking time to offer us your thoughts. We look forward to seeing you again soon.
Kind words, I really doubt the absence of password entry was any kind of oversight or accident."