There are also the taxpayers that need the government pension funds to make good on investment assumptions, lest taxes have to go up.
Edit:
Politician A: I will remove all deferred compensation schemes, but have to increase taxes to pay the employees with money today
Politician B: I will pay the employees with deferred compensation, and keep taxes lower than politician A, and let future taxpayers deal with any problems of underfunding and corruption
Politician B wins every election.