Bushes aren't randomly offset, unlike similar blocks

Bushes don't have the random offset when placed, unlike similar blocks such as grass or flowers.

How to reproduce

1. Place around 8 bushes along a line of grass blocks.
2. Place around 8 short grass along another line of grass blocks.
3. Notice the difference in placement.

Expected result
Bushes would be randomly offset, similar to other foliage.

Observed result
Bushes are fixed to the center.