What I expected to happen was...:
If the player has the spawn eggs (or other entity summoning items - like boats & minecarts) in their inventory whilst in survival mode, using pick block on entities should move the spawn eggs (or boats, minecarts etc) to their current hotbar slot (or change their current hotbar slot if they are in a different hotbar slot).

What actually happened was...:
Pick block does not move entity spawning related items from your inventory to your current hotbar slot, or change your selected hotbar slot if the entity spawning related items are in a different hotbar slot, whilst in survival mode.

Steps to Reproduce:

**1. Make sure you are in survival mode.

2. Obtain an entity summoning item like spawn eggs or boats and minecarts etc. (via any means necessary)

3. Spawn the entity.

4. Place remaining spawning items into your inventory or a different hotbar slot (not currently selected).

5. Try pick block on the entity.

6. Result: items for summoning the respective entity, are not moved to appropriate hotbar slot, and hotbar slot is not changed if they are in a different hotbar slot.