It can be used on allied pack animals like Muffalos, they will be tamed instantly with their inventory now belonging to your colony. There's no relations hit with the faction whose animal you stole, and you can unpack the gear infront of them to haul to your stockpile, they don't care.

I did this with a Tribal Bulk Goods trader, not done it to other traders yet, I assume it'd work the same way. Very easy way to get endgame stuff without conflict early-on.