There seems to be quite a few things that are non classical about bandits.
Only human bandits are supposed to drop bandit sashes, and they can also drop bronze weapons. The barbarian and caster bandits are not supposed to drop sashes, or bronze except for a few different weapons. If I remember correctly the only bronze weapons that the barbarians dropped were bronze two handed swords, bronze maces and bronze battle axes. Humans dropped bronze spears, bronze rapiers, bronze shortened spears, and bronze main gauches. This appears to be happening in West Karana, and East Karana. I can only assume that it is that way for bandits everywhere.
http://eqbeastiary.allakhazam.com/search.shtml?id=364
There are some posts in here about people saying the humans only drop sashes and bronze. It was the only info I could find.