That's what's going on in the other thread where some people are criticising Linus and some others say that he's not paid by them, so shut up.

My opinion is that even you're a volunteer, you should listen to criticism or don't call yourself a volunteer (as this usually means that you want to achieve something for the benefit of others (at least in part), or you're doing something in cooperation with others). If you're not completely isolated then your actions have an effect on others so you should be prepared for criticism.