Same reason SWA has a crew base in both locations.

Lots of overnighting airplanes plus flying there prone to IROPS/sick calls/chaos. Lots of pilots that live in the area that can help recover the operation in a meltdown scenario.

Those two things alone make it worth it to keep a small crew base open and staffed. UA has a coterminal in TPA for the same reason. Anyone who has tried to drive that stretch of I-4 anytime past 1pm knows what a nightmare it can be, but lots of pilots live near TPA, so it works fine.

I think the notion that they opened a crew base to make pilots happy or attract/retain pilots is honestly hilarious. I guarantee it isn't even a consideration.