I saw these cars twice, in the 90s they were casually displayed in the local BMW dealership like normal used cars.... very weird.
No fences, no guard, just sitting there, Warhol, Lichtenstein, Calder, Stella. °_*

The set above is from an art exhibition in 2006, with personnel but still open in public without any fence or such.
BMW were relaxed despite the value of these cars.