This whole thread is absolutely ridiculous. Grandmasters want students who are dedicated to improvement and who will take chess seriously - they don't want a student who will waste both their own time and that of their teacher. It's not all about money; they want to feel like there's some progress or purpose behind their teaching and that their students are committed and will listen to their teacher. When you're one of the best players in the world you deserve to be picky about choosing students (more so as one of the far rarer English-speaking American GMs in the world). If you want to work with the best you have to have aspirations to be the best you can be or both of you are wasting time. There's no discrimination in a GM (or any coach!) not wanting to teach a student who doesn't trust them or refuses to give them basic information. Private tutors can choose whoever they want.
Do you like to teach french to older persons even when they don´t progress that fast? or it gets to be frustrating?
At the moment I'm happy to teach anyone who is willing to try to learn, and although I do get frustrated sometimes, I understand that people learn at different rates and that if they put in the effort, they will improve. At the moment I'm just looking to become a better teacher so that when I hit NM I'll be able to establish myself as a coach.
Try telling that to a martial arts grand master... he must teach you or else... that will go over big. *snicker*
Any martial arts master worth a damn would simply tell them they aren't mature enough to use the teachings appropriately... or else they may use them for nefarious purposes (e.g., beating people up, starting a for profit strip mall martial arts chain, etc.)