Vendors and Owner's rights

[Pringles]

Only problem with this is, if the owner never visits them ever again, they don't fall until they run out of money

True, that's why on SA the staff removed vendors of unfriended players outside of building if a player didn't talk to the vendors after being unfriended.

I haven't found any information about what the policy back then was of GMs regarding this issue. And since I didn't play during this era,
I do not know if GMs helped with this or not. I think they did though, because on a later date OSI implemented vendor contracts, which made GM intervention not needed anymore.