It's not just that people can "write their own tickets", but that promotions and raises seem to happen much more at time of hire than after good performance. Work on that and there might be a lot less churn
I've encountered these, and I'm told they're pretty loud.
I'm a fairly young guy (37 yo) with perfect hearing below about 1500 Hz, and almost zero hearing above 2000 Hz. To me, these loud clicks are tough to hear unless close up.
I run into the same problem with high-pitched fire alarms (most of them), the "you left your headlights on" beep, seat belt beeps, kitchen timers, the little beep on my FasTrak transponder, etc.
This is probably a widespread problem--we tend to lose hearing in the higher frequencies first. The solution isn't to use annoying high pitches and make them louder; the solution is to use broader frequencies or use lower pitches that more people can hear.
Please keep this in mind when you're considering using a little chirpy piezoelectric in your next circuit project