I have just remembered a case like this in a building in which I used to live where a tenant told a friend he could park his car in the block’s garage while he (the car owner) was away in Europe for six months.
The EC ran around in circles trying to find out who was responsible and I think it was only when a notice was sent to all residents saying that if the car wasn’t removed within seven days that “action would be taken to dispose of it”.
It wasn’t exactly an empty threat but there was nothing they could legally have done. There was no comeback on either the tenant or his mate because the former hadn’t breached any by-laws and the latter didn’t come under by-laws.
It strikes me that it would solve a lot of problems in strata if everyone who sets foot in or drove into a strata building was told that they either accepted they were subject to strata by-laws … or they could leave.