Some useful tips to avoid bugging:
- Don't drop food by the ones that are standing in a big clump and not mining (you don't see the picks moving).
- Make sure that there's at least two or three peons in each camp, so don't put one by a solitary peon because that's probably someone who did the booterang quest.
- Drop the meat an equal distance away from all peons (see note below)
Note: I'm pretty sure the "bug" lies in the position of the little haunch of meat relative to the peons. The "event" that occurs to give you credit for the camp is only started when ALL the peons in that camp (two or three of them) have run up to the mutton. If you place the mutton to close to one of the peons in the group, all the other peons will run towards the mutton except for the one that's already "close enough." Unfortunately, it seems that the "I'm close enough" check doesn't trigger the "I'm at the meat" check, and that peon never moves. The other two peons will typically clump on top of that peon, creating the "bugged groups" that you often see.
Solution: Make sure there's a decent gap between any given peon and the mutton you drop. You can stand a few yards away and still get them all to run. Just don't be hasty and drop mutton on top of a peon, because that will probably result in the bug.
I've done a little testing, but if anyone feels like wasting some glands to test this, feel free :D