Yes, not surprising it is in their contracts to have some sort of financial penalty. Anymore, most airlines have some sort of bonus/malus program with their vendors. Some international carriers have built in that if there is a delay caused by the ground handler, it's a sliding scale all the way up to an hour delay basically means they got that flight for free (which can be thousands of dollars on a widebody). With many contracts within the US between airlines and the ground handling vendors, there can be penalties (or a bonus) assigned to each goal and there can be 8-12 goals monthly. Penalties can be even as high as 5-7% of the monthly bill, and that's a lot considering the margin on these things is usually around 8-10% to be competitive.

I had a Delta station manager explain to me once how their station made their 20 minute to claim goal... they figured out they didn't get in trouble for sitting a plane out waiting for a gate for 15 minutes, especially if it arrived early. So they would let planes sit short of the gate until they had enough people to throw at it for 10 minutes to hurry up and get all the bags offloaded (like 5-6 ramp agents). Back when check-in kiosks were a new thing in the late 00's many airlines had goals for percent check-in via self service. A lot of airline stations had their closing agent, while waiting for the nightly terminating flights, take a manifest and stand at a kiosk checking in everybody for the next morning. Amazing when you set a goal and suddenly compliance goes from 20% to 80% in the course of 60 days.

But on the bags to claim with Delta... that vendor and its employees have more incentive. Insource Delta station is gonna get yelled at. Outsourced station is going to take a financial hit, and probably result in suspending agents to "pay back" the handler.