Greed??
I reckon that players should take what they can get. And if that means moving on to another club where they will be richer/happier/etc then so be it.
Clubs will drop a player in the blink of an eye if it suits them. Clubs will pimp players to the max to earn a buck. Clubs are only in it for the dough.
Players know this, the fans know this, but still players are expected to show total loyality.
Plus, why shouldn't a player do whatever it takes to protect his/his family's future financially. By the time he's early to mid 30's that's it, game over. Then they've got another 40-50 years of trying to fill their lives with things to do.
If someone came up to you and said "Right.... you will be recognised and taunted by many people every day, you will be stared at or approached where ever you go, and everything in your personal life will be analysed to the max, and finally... after your 35th birthday you are not allowed to work again............. how much money do you want to be subjected to all this??"
I'd want £10 million please. At least.
And if someone offered me £40 million, I wouldn't turn it down, even though i'm PROBABLY not worth it.