I think that it is because they're from working class backgrounds and the fact that it's football, alot of people seem to think that it's just 'kicking a pigs bladder in a muddy field' they don't seem to understand that it's one of the most difficult professions to become successful at on this planet, also, because the general public are removed from the other professions you mention then they don't really comment on them. I've seen people compare a nurses salary to that of a footballer, like it's relevant. Ofcourse nurses should be on more, it's a completely separate issue. The working class do like to attack the working class.