Why would I leave them a brand new refrigerator? The economically rational course of action would be, on moving out, to put the refrigerator that came with the unit back in place, while I depart with the refrigerator that I purchased with my own money. After all, the unit's refrigerator died of old age while I was occupying it, I didn't do anything to it, and shouldn't be liable for replacement costs. Just store the failed appliance intthe living room until I move out.

Letting the landlord replace it a year later than they otherwise would have saves them money!