Players should gain moral when being transfered

A lot of times, when you buy a player, his moral is down, because he wasn't playing at his club.
The thing i don't understand is why is he not happy to change team ? I mean, this probably means that he will have a more important role.

I know it's a minor suggestion, but i still think it should be added :)

The better question is "What is it that affects moral? and Why does moral diminish overnight?
Many times I have used moral boosters to get players to superb condition and in the morning they just get back to very good.