Professional football is a cutthroat industry for players. For all the talk of player power Roy Keane wasn't far wrong when he talked about how clubs treat them. Their only deemed as valuable as the benefit their services can provide, and for footballers that rarely strays too far into their 30s. However Fletcher's fitness progresses, we aren't going to give him a pension. He'll be out on his ear in his mid-thirties anyway. A time when every other man in the world should be hitting their prime.
It's the kind of scrapheap challenge that sent Gazza off his axis. Anyone assuming Manchester United or any other club will continue to employ a player, official or any other mother for significantly longer than their use is beneficial performance wise or economically, is being naive.
They may be some vestige of loyalty keeping him here, but it'd be more heavily tilted towards what a re-couperated match fit Fletcher could provide on the field, and not an overly romantic sense of duty and patronage.