Another example is allowing the employee preferential access to overtime in the last year, or them exercising unused vacation time as a one-time cash payout on retirement.

The overtime thing is the most galling, since it's generally straight-up theft of government resources. There's no legitimate government purpose to the extra hours. The theft is culturally accepted by government employees because it costs more than garden-variety timecard fraud -- you don't just get to steal the marginal hour's pay, you get to steal X0% of that every year for the rest of your life, automatically. And it becomes culture in these institutions -- you cover for others because you expect someone to cover for you once it is your turn.