They’re not putting anyone in danger. They are causing a possible delay in the response to a potential danger which is extremely infrequent.
If someone is having a heart attack , every second counts, thats why many places now have difibulators onsite. ANd while its infrequent that things occur, it does happen enough to make a differnce. Most of us have been in shul at some time when Hatzolah needed to be called (or whatever they use in Israel)