why do places that are open 24/7 365 days a year have burglar alarms?
maybe for panic buttons to press if they get robbed.
The facility likely had a system already installed when the 24 hour business moved into the space. Plus, there could be mechanical or stock areas with daytime coverage to prevent unauthorized access.
Just because they are normally a 24/7 operation doesn’t mean they couldn’t never close and lock the doors if they needed to. A weather emergency, natural disaster, power failure, or other emergency could force them to close/lock the doors and vacate the building. The company would want their building protected from burglary in that case. Also, like Chris said, holdup buttons. A lot of retail operations also have 24 hour armed doors - emergency exits, loading dock doors, roof hatches, and counting rooms for example. Before opening one of those doors, someone has to enter in a code into the keypad to keep the alarm from activating.
To add one odd example… We used to service a grocery store. They had normal business hours for the public, something like 7AM-11PM. But during the overnight hours (11PM-7AM) they would do their stocking and cleaning. So there was always someone in the building. With the exception of two days a year - Thanksgiving and Christmas Day. During those two days, they had a burglar alarm system and armed it. We always went out there the week before Thanksgiving and checked the door contacts, sent test signals, checked batteries, etc.
Connection to facp for a dialer