How strict are you when giving out fines and warnings?
I'm actually quite strict with my players.
A Sending off during a match = Fined 2 weeks wages. I never give a warning or appeal.
Poor Performance = A warning the first time, if it continues again, Fine 1 weeks wages.
I feel like my dicipline has killed morale though as my keeper performed horrible and I gave him a warning. And he dropped right down to Very Poor.
But I have noticed that some players really don't care about losing wages because they end up getting sent off again the day back after suspension.