Just an interim report. There seem to be 2 different avenues coming out here .... groups and 1/offs.
In regards 1/off travelers, as an experiment I tried flushing the kitty litter bag contents down the regular toilet. Not good. First off, as Angie said "never flush kitty litter down the toilet", and certainly you'd never want to dump a regular 5-pound kitty litter tray that way. But I figured, what the heck, there isn't much kitty litter in a poop bag. Well the problem seemed to be that the kitty litter dried out the poop enough that it didn't just go swirling down the drain as normal. So ixnay on kitty litter bag in the regular toilet.
For that matter, this is why my "first" experiment with the toilet used the solution of cooking oil and dish detergent, rather than kitty litter. So probably cooking oil isn't the best ingredient to use in the bag, but detergent ok. So, for me, this is a viable solution when camped with some access in the area to a regular flush toilet. Detergent in the bag helps keep both the bag clean for disposal in the regular garbage, and also the toilet clean. I would not want to store the filled bags for very long of course.