Works as intended Settlers to enslave already collared

[Agi_]

It happened in two enslaving attacks, after the first one where Jammer tells you that you can build collars at the chem station.
After wining the assault all settlers were already collared, no use for those i had with me.

 

[kinggath]

That's normal. When doing an enslave attack, all of the settlers will be collared for you.

The collars are meant for taking slaves from your Vassal settlements, and now as of patch 4.0.3 you can use them on just about any non-unique human or ghoul NPC in the game.