Because it was not financially acceptable to Uniden to include coverage for a band almost nobody would use.
I've always wondered why that is. Does the FCC charge for certification by the megahertz or what? Seriously!
Coverage gaps used to bug me too - I've got a perfectly useless BC895 that I can't even turn into a Unitrunker scanner because it won't tune any 700MHz control channels (Neither will my $500 BC796D, which I also was a little miffed about).I know, I know they weren't type accepted for it and so on, but they are also older than dirt at this point,so what's the harm in releasing the firmware spec and letting us play around with 'em? About all I use both radios for now is to keep the spot underneath them on my dresser dust free.
There's still plenty of analog to listen to and such, so I can use 'em for that, but you get the point - I'd much rather let that old workhorse 895 of mine chug away on a control channel or two and log stuff. It's already tapped, just needs the ability to tune the 700MHz band. Alas, it probably never will. Meanwhile my cheapie little $20 RTL dongle can tune it and lots of other places none of my far more pricey scanners ever could! That's just one of a growing list of reasons why I'm moving away from scanners and into SDR.
-AZ