And who knows how many of us might have contributed to similar schemes. I've bought self published books from Amazon for a couple of quid that have been so terrible I've just abandoned reading them. The price is low enough that I just write it off and move on. Generally a sensible approach for one's peace of mind, but, of course, if tens of thousands of people do the same the 'author' will potentially make a lot of money.
We've seen examples of plagiarism happening that are effectively doing the same thing. The difference with them, of course, is that they are quite likely illegal and liable to suing whereas just selling a load of garbage is not, technically speaking, illegal.
It's pretty scary that he managed to get away with it on such a large scale.