It's not really a matter of being able to afford it. I think most people can afford whatever they want (within reason) if it's high enough on their priority list. I don't really think I can afford a car but I do have the cash to buy a relatively modest one outright if I wanted to badly enough. I suppose e-book readers have an advantage over PC's in that they really don't go obsolete. An e-reader that can display an ePUB now will still be able to do it in 5 years with no change in performance. PC's on the other hand degrade significantly in performance as software changes.
I just don't want to go out and buy a Sony 505 only to find out that in 3 months time they release the brand new Sony 705 with super duper Epson controller speed or something like that