Indeed, that's the case here in Bucks County, PA, where we have a 500 Mhz Morotola Astro system, and as I recall encryption is a trivial addition to the system.

On the one hand, as a civilian, I like being able to hear what's going on, on the other hand, as a responder, it can be a bit frustrating to have "flash crowds" around a call because someone hear the call on a scanner and text messaged a bunch of folks to "go check out the meth lab bust" - so we end up with a lab bust call AND a crowd to be managed. I don't have the people to deal with it.