My mum worked in an upscale retail store back in the day when they introduced the first version of that system. As you say they went of on customers all the time, so she or a coworker would be ready with a box chocolates and an apology. This wasn't cheap at all, but it was still worth it because it prevented so much theft.

I don't know if that is still the case, or it is just that thieves go for the easy stores that don't have any security. Back before reddit banned r/shoplifting I lurked there out of curiosity, and it seemed that those who posted there had pretty good ways around that security.