As jordigh points out, RMS has always been quite happy to charge money for software. For example, the FSF sells a $5,000 "Deluxe Distribution" compiled for a platform of your choice:
http://gnu.ist.utl.pt/order/order.html I've spoken to various people at the FSF, and they're generally quite enthusiastic about charging money for GPLed software.
But to make a larger point, if you try to model RMS's behavior using cynicism, you'll tend to make inaccurate predictions. To use a metaphor, his brain is running slightly non-standard software: His social skills are not quite compatible with standard protocols, but he will go to far greater than ordinary lengths to uphold his personal moral principles. I've dealt with RMS and/or the FSF a couple of times, and once I decided to assume that RMS wants exactly what he claims he wants, dealing with the FSF was actually rather pleasant.
Thus, if Stallman thought that programmers should live ascetic lives, he would have written long essays justifying why this was correct. But instead, he wrote long essays about why sharing and hacking on software was a Good Thing, and added (almost as an aside) that you are welcome to charge as much as the market will bear, and that doing so may often be a good decision.