Well 100 appearances is a big milestone for a player. It symbolizes his loyalty to the club and a player that reaches this should gain some kind of boost in skills a new position of our choice or a special ability. Come on, players feel so lifeless and this will give them more personality and leave the mark of the team they are playing. This could also be a good start to the implementation of the so much requested club history.
The problem is nordeus don't want to encourage player loyalty, they want you to buy new player with tokens and money. You have to remember they are a business.