Baby Stealing vs. baby sharing/swapping

I'm confused - and that should not be a surprise to anyone. I'm not a breeder and I don't pay attention to a lot of the discussions breeders have because I think "I will probably never deal with that." Not that I thought I would never have babies, but that I don't think I will have them repeatedly or even frequently enough to experience the number of things a breeder does. BUT, I have heard many people talk about baby stealing when they have a trio. It is always talked about negatively. What does that mean exactly?

Here is why I ask
I have a trio that just had babies. Both girls had twins. I routinely find Kibble's babies in Tid-Bit's pouch and Tid-Bit's babies in Kibble's pouch or one of each in each pouch. I never find all 4 babies in one pouch, but some times Tid-Bit will have 3. That usually doesn't last long. LOL
Neither girl seems to mind ever. They just see a baby wanting to nurse and take care of it.
This is the first time any of MY babies have had babies, so I am new to all of this and so excited and happy and worried and so on. But, they seem to know what the heck they are doing.

So, is this what is meant by "baby stealing?" and if so, is it a bad thing? If not, then what are you breeders talking about when you say baby stealing?

baby stealing in when one female eats the other females babies out of her pouch...

and what you see happening is normal with trios from what I have seen

That is an excellent question, Val! I have never had any baby stealing here, but in the very beginning, I did have a trio: Sugi (dad), Tink (mom), and Loki (mom). They were all actively involved in "shared parenting" - each helping the other. Sugi was a great little daddy, and once, when Tink had a dingbat moment, and she dropped Baby B, Loki and Sugi kept that baby warm until Tink wisened up (Sugi and Loki crabbed their heads off at her). Then, "ding-dong" Tink came back down and picked Baby B up, and off they went to the pouch. This was one of the coolest glider moments I've had with my gliders. I only wish I had had it on video, you would have to have seen it to have believed it. Sugi and Loki DID surround that joey and keep her warm.

I think that baby sharing would be perfectly normal in suggies that are oop around the same time. But then again I'm not a breeder either and have not experienced breeding trio's.

A perfect example is that with my farm cats if litters are born with in days of each other, ALL the momma's share the kittens. And they do it exactly how you described your 2 momma's are doing with their joey's.