Ha ha. I can tell you that for the most part the answer is no.
Besides, musicians who DO obsess about sound quality ARE audiophiles, so I guess the question is kind of flawed in the first place.
I was going to say the same thing that if they do care that much about the sound they are audiophiles.
But I understand what the question was trying to ask and I'd say there is absolutely no general answer. Some do some do not.
I also agree with the person who mentioned the apple earphones. I hate those things. The quality is subpar and I never understood how people in the commercials can move around without them falling out.
I enjoy the nuances within the music myself but am not obsessed (not an audiophile) to the point of pumping up my system in either my house or car. (mostly due to money) although my car stock stereo is pretty good and my house I have 5.1 surround on my entertainment receiver and my computer.