yeah.. I remember seeing some good size disposable ones a while back. like baby bottle size. had a stiff plastic housing and you filled it with small bags just like they did for a while with those throwaway baby bottle inserts. even one of those would work if you could mix it and get it in the bag and then shoot it in the car fast enough.

in any case, it's going to be a pain.. but the benefits of the heavier duty stuff definitely make it worth the extra hassles.