Pillagers can shoot you in creative mode and spectator mode

Pillagers can see and shoot players in creative mode and spectator mode which i suspect is a big issue since players often use spectator mode to spy on other players in their server, and those pillagers can give them away.

But the pillagers will only see the player if they were previously seen by the pillager.

What I expected to happen was...:
I was expecting to be invisible to the pillagers as with all other mobs in creative/spectator.

What actually happened was...:
The pillagers saw right through my invisibility and gave me away.

Steps to Reproduce:
1. Simply be seen by a pillager.
2. Go into creative/spectator
3. ???
4. Profit.