This is very likely working as intended due to how MC-243081 received a Mojang Priority. See the description of MC-243081 for an explanation as to why it makes logical sense to have the sounds of throwing eggs controlled by the "Players" sound slider.
What I expected to happen was....
When I change the Friendly Creatures volume, all items that can be thrown (eyes of ender, snowballs, ender pearls and eggs) play the sound at that volume.
What actually happened was....
All items except the egg are affected by the volume change
Steps to reproduce:
- Go into Settings
- Go to Music & Sounds
- Change the Friendly Creatures slider so that it doesn't match the others
- Use any of the following items: ender eye, snowball, ender pearl
- Throw the egg
- Notice that the former items when thrown respect the volume you have set, while the eggs do not