Why is bonemeal disabled for grass in the first place? It's not like people are gonna use it to grief. It doesn't hurt anything. We have WORLDEDIT ffs. If anything, bonemeal on moss should be disabled, since it actually replaces blocks. Nobody's gonna join the server and think, "oh yeah i will bonemeal a bunch of grass to ruin everything. im so evil! hahaha!!!"
I doubt this suggestion will even be implemented, considering last time I posted a suggestion everyone agreed to, it was forgotten about anyways.