The Kindles sold by Waterstones got a firmware update in early November. This update wasn't rolled out to all the Kindles, and for good reason. According to a couple different users (story has also been confirmed by Waterstones) the only change in the update was a new screensaver.
I have not yet seen it myself, but the Kindle owners are reporting that all the screensavers have been replaced by a Waterstones logo. Furthermore, there's no way to disable or replace that screensaver, so every time these Kindle owners pick up their device they will be reminded where they purchased it.
Apparently Waterstones thinks their customers are stupid.
You would have to think your customers are stupid if you assume they won't do the math, realize they paid full price, and be pissed about the advertising. And it is advertising. This is just as much an advert as the ones found on the Kindles w\SO, only Waterstones' customers didn't get a discount on the price.
You would have to think your customers are stupid if you think they won't return the Kindle and then go buy one (without the advertising) direct from Amazon.
Rude comments aside, that is exactly why this was a poor decision. Waterstones takes a commission on ebook sales, so they should be doing everything they can to draw in customers and not be giving them reasons to abandon the chain.
P.S. For those who are interested, here is the email which Waterstones sent out to one customer:
Thank you for your email regarding your Kindle Paperwhite from Waterstones.
I am sorry you are disappointed by the addition of a Waterstones screensaver after the recent software update to Kindle. It is our view that this screensaver does not constitute advertising and differs substantially to the advertising-supported Kindles available to the US market. The Waterstones screensaver is a non-dynamic, static image that will change infrequently and not advertise any specific product, offer or website.
It is not possible to remove the Waterstones screensaver to replace it with the former Amazon screensaver. We apologise that this change was made without consultation, and hope it does not detract from or alter your reading experience. However, if you feel it does, please let us know and we will arrange for the return of the device and a full refund.
I am sorry for any inconvenience this has caused.
Customer Service Team