Our local PD had a clearing pipe at their indoor range. Strangely, the rangemaster didn't require civilian shooters to use the clearing pipe because the range rules required you to carry guns in/out cased and unloaded.
It was for their officers, who were supposed to clear before entering the range and then load on command during the training exercise.
Apparently they just weren't that practiced at dealing with the "round still up the pipe" condition and every month a few would rack the slide, drop the magazine and pull the trigger with the muzzle in the clearing pipe...Bang.
I don't own a DA semi-auto, but I would imagine it should have been drop the magazine, rack the slide, then pull the trigger.
If someone had some kind of daily routine like that (which would introduce questions of bullet setback from repeatedly chambering the top round, how to rotate it, etc.) I could see some benefit from having a clearing bucket located where the individual "cleared" the gun when they got home.
Otherwise, it seems a useful device for institutions that deal with large numbers of armed staff, and the placement seems to be at boundaries where their operational rules require guns to be cleared for some reason.