Leaves/Flowers obtained by shears do not stack with those by silk touch

Leaves and flowers that are obtained by silk touch do not stack with those obtained by shears. This also applies to enderman drops, although I don't recall which class their drops are in (silk touch, I guess). You can set down the silk touch leaves and shear them to get them to stack, but that's not practical. It does not work to throw them all on the ground as it has in the past with other items which should stack but don't.