Probably less chance of it being vandalised if it was open tbh.. it’s more likely that someone would walk past an empty shop with the shutters down, and throw something etc than it would be for someone to do the same while it was open with staff and customers inside, and security on the door.
Our shop at St Enoch only ever got vandalised when we were closed, either during the night or when we were closed during lockdown. Never once when we were open.
The tims will ofcourse know this, and are probably looking for something to happen to play the victim.