I was really tempted to pick up the barrels that had kobolds in them and go and sell them to Lady Esther, but I decided to let them out because they net so much XP. Maybe next time...
I store them away. I don't know, but I hope they'll happily live forever sitting in barrels in my Tardis-chest in camp. I was wondering if I could throw them and have them burst and attack an enemy, but never tried it.