I can answer why I do this, and I know it drives my husband nuts, too. FIOS TV has a crap menu and program guide, and I've never been able to figure out where the HD channels are. I know what the regular channel #s are, and they're (mostly) clustered together where it's easy to spin through them to see what's on. The HD channels are all over the place, with a bunch of crummy channels or channels we aren't subscribed to in between. The only thing I regularly choose HD for is when the Spurs are playing.
If anybody has FIOS, is there a way to remove all the unsubscribed channels from the on screen guide? I can't figure it out.