Interesting this. It's funny how when you look back now at pro-footballers in the 60s or 70s who were smoking, drinking, etc it's deemed as somewhat cheeky and mischievous yet now they are seen as more disrespectful.
I recall Ashley Cole missed a training session a few years back and apparently went AWOL. Someone raised a point about Billy Bremner doing exactly the same many years ago and the general tone of the media was a humorous one as opposed to one of discontent. Funny how mindsets change.
Its the money.
When players were being paid a wage that was a bit closer to that of the "working man", then fans could relate to those players more and endulge them in a few off-field misdemeanours.
Nowadays, when a player is paid more in a week than some people can earn over the course of 10 years, fans are probably entitled to expect a bit more professionalism from them in return. Part of it will be good old fashioned jealousy as well of course.