Falling entities drop as items when falling on non-solid blocks, even when gamerule "doTileDrops" is set to "false"

When you type the gamerule doTileDrops and you place a sand on top of a torch the sand will be dropped.
I think its need to dont drop.
1. Type /gamerule doTileDrops false.
2. Place a torch on the floor.
3. Place a sand up to 2 blocks.
4. The sand will be dropped.
Thanks.