Here's my guess. There was a decent incentive payout, which is why they explicitly mention the +$6m. Some idiot person in HR thought this "mint" play on words would be clever without realizing how it would be exploited. By people like you.
Here's my guess: this is a prison warden thanking his inmates for the slave labor that helped his investors profit off of the prison industrial complex. This is fun! I like making shit up with you.