[BH] Customers leave shop through non-public areas

I am having a similar issue.  So one of my employees set fire to the cooker.  No harm done other than needing to replace the cooker and counter next to it as I have the alarms and sprinkler system on the lot.  But this customer has come in through the doors after the fire and just raided my sims fridge - without paying!  And no it's not a disruptive customer, just a regular customer. Attached screenshots.  You can clearly see she's a customer and you can clearly see the area is in yellow for employees only.  I am going to try and lock this door now for employees and household only but really shouldn't have to. 

Edited to add, I do not run mods. 

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