Possibly, I hadn't thought about that angle. Great point.
I was thinking it was a combination of just making sure they had enough bodies for the game, plus giving those three a year end bonus via a nicer paycheck this week.
As soon as the season ends teams that missed the playoffs sign practice squad players to Futures Contracts, which prevents another team from swooping in and poaching them. Since these guys will finish on the 53, they are now under contract through the end of the league year and don't have to be signed to a Futures before somebody else swoops in.