No curved half-wall crenelated variants for mushroom bricks?

Every material that can be turned into walls has a half-wall crenelated variant, and yet only grass planks have a *curved half-wall crenelated variant.

Ummm... why? Was this overlooked, or do they really expect people to not want these vital construction methods. My castle looks so lame with completely flat curved towers when the rest of the castle has gorgeous crenelated walls.

Help.