Pinballs at campgrounds aren't as rare as you might think; I've seen them several times in both the US and in Europe. Lots of better campgrounds have game rooms, most with stuff other than pinball, but pinballs do pop up in a fair percentage. Sadly, many aren't properly maintained and not worth playing. Always inspect the machines at such places before dropping coins in.
One of the strangest places I've seen pinballs was in a dark hotel basement in Switzerland during a business trip in 1996. They had playable Genesis and Comet. There was no mention of "game room" anywhere in the hotel information, they'd just put them down there for someone's amusement and guests were allowed to use them if you stumbled across them.
I've also seen many "theme" games in suitable locations - - Fire in a Firefighters museum, Ripleys guess where, Whitewater and Waterworld in a car wash lounge, etc. At one time, there was even one in Death Valley, a Cyclone at the main hotel at Furnace Creek.