Just to be clear -- I wasn't commenting on whether the diversion in the OP was appropriate or not. I was just pulling the $188,000 figure from it so we have a rough idea of how much a generic diversion costs.

Air rage (when the person cannot be adequately subdued) and medical emergencies sound like very legitimate reasons for diversions. Bottled water smuggled onboard by a passenger, a bathroom that none of the FAs can remember which of them locked, Middle Eastern guys playing around with their cellphones, and the dozens of other diversions we've had since 8/10 are a very, very different story.