Japan has civilian flying clubs, and non-government (not fire department, police, &c) gliders and light planes crashes are unfortunately common.
https://follow.yahoo.co.jp/themes/06de47c4daa840ed9717
For example, this is the Yahoo! Japan News tag for aviation accidents.
The most recent accident is 2017/08/14, when a civilian light plane crashed in Nara Prefecture, with two fatalities.
OTOH, retired warbirds are rare.
Some resourceful civilians may somehow acquire retired JASDF planes (F-104, &c) from scrap yards, and display them on their roofs.
Worse, WWII IJAAF/IJN warbirds displayed at museums, and not at air bases, are mostly wrecks, or 1:1 replicas.
Here in Hong Kong, I read rumours that some surplus Spitfires retired at Kai Tak, were pushed as landfill into the water, when Kai Tak extended its runway into Kowloon Bay.