You are not buying the books so much as you are buying the application. You are paying for the work the developers put into making a really nice app to read books with.
If you think it's overpriced it's your right to voice that opinion as well but try to be civil; if you don't like it you don't have to buy it. Remember there are going to be things you like and others do not so would you want them attacking the things you love simply because they don't?
Now if you have bought it and it sucks then tell us that too, that's helpful, but otherwise no one really cares about anyone else's non-fact-based opinions.
If you think it's overpriced it's your right to voice that opinion as well but try to be civil; if you don't like it you don't have to buy it. Remember there are going to be things you like and others do not so would you want them attacking the things you love simply because they don't?
Now if you have bought it and it sucks then tell us that too, that's helpful, but otherwise no one really cares about anyone else's non-fact-based opinions.