It's a great way to spend money...that's about the best answer anyone has come up with. Sure, it may have it's uses, for sensitive calls and conditions, but for the most part, it's radio salesmen scaring people into buying it, just like telling them when they narrowband that they have to go digital.
In my state the ODNR is full time encryption (might need to discuss sensitive squirrel and woodchuck information) but the Highway Patrol is not...nor are 99% of anyone else. Toys and Trends.
When I was working in radio we had a gravel and sand hauler who working a 100 mile radius basically, and they had AVS boards in their MOSTARS and Radius radios....Only people I knew of in our entire 15 county area that had "scrambling" (exception being a Sheriff with VHF who had DVP-XL, but rarely used it) so I asked the owner why....he said "to piss people off". (so much sensitive info when it comes to delivering gravel....)
Heck, our SO has a TAC repeater...and no one knows how and when to use it...let alone the monkey & football we would hear if they actually had encryption.