It is not that uncommon. They do make for interesting stories though...
Back in the early noughties there was an AN-124 parked at EHBK for years. It had passed through multiple sub-leases to various dodgy outfits in the former Soviet Union - its most recent sorties had involved flying duty free European cigarettes into Kazakstan... needless to say the operators saw airport fees as an optional cost and as soon as they had made enough flights to retire, they disappeared... Eventually Antonov itself stepped in, flew in a new set of engines, pumped up the tyres and flew it home.
(Over 5,000 people watched its departure. I can only assume in case it crashed after so long on the ground.)
In CYQT a 747SP Global Peace Ambassadors biz-jet suddenly appeared, fleeing US creditors. It too sat around for months, then just as suddenly vamoosed. Seems they cxl'd their flight plan and flew it (VFR!!!) to Mexico where it sat in the desert for long-overdue repairs. It was the one the Chinese took supersonic - apparently it never flew straight afterwards!
If only planes could talk...