Indeed. Unfortunately you are not alone with that problem, it can happen easily.
It is very easy to bend it and thus break the screen.
To be very honest, I think that the newer ones are even less stable (thinner housing).
It has to be said though, that Amazon normally is very good at replacing those when the damage happens early in the products life. Try to call the Amazon Kindle support, maybe they are able to offer you some option (e.g. a deal on a refurbished one), or you might get a used but unbroken Kindle 2 at a good price at eBay.