My waterfowl guns are all SxS extractors. The empty hulls go straight into my pocket, new ones come out of a fanny-pack worn on the front. I reload some but not all hull types, regardless they all come home with me.

The problem of spent hulls as litter is not severe in the monsoon tropics where I hunt: dry-season grass-fires melt the plastic and anneal the 'brass', and subsequent wet-season inundation rusts or rots whatever is left. Its rare to find a hull more than a year old, despite the fact that most waterfowlers (sadly) drop them at their feet and walk away.

Marrakai
http://www.hotkey.net.au/~orrs/Marrakai