You should basically ignore this advice. It is a wild exaggeration, although there are occasions when you will still encounter such a response, but the norm is quite different.
If you're searching, go to Jimbocho (by subway) in the Kanda bookstore district of Tokyo. You will find quite a few magazine shops that are filled with -- shall we say -- advertisements. Some of the best shops are just off the main street. Of course, if you can't read Japanese, it's a little more difficult. But if you can't, you should still be able to understand the numbers to get the price, and if what you're looking at seems good, go for it. But then, when you get there, if you can't speak Japanese -- well, it could still be an adventure; some things are understood without speech.
