A nice new change of scenery does seem more fun then sticking to the same old same old. And I think some players see club play more as for fun and experience. The real rewards are with their NT. But I guess it all really depends on the type of player you are.
It also shows how good a club really is if you can win with a different set of roster year after year.
Exactly! It's good to see players changing things up. Money should be the key factor when it comes to clubs, yes, but living in different places and playing/getting to know different people might be important to some of them as well. Transfer season is my favorite and I really like to see teams and tournaments with fresh faces. Watching the same team with the same squad for too long gets boring.