There's a lot of assumptions there.
I am going BASED ON THINGS THAT HIS GF TOLD ME. She has complained a lo about wanting a primary, children. and putting pressure on my husband.
I don't want her to be part of my family, but some appreciation would be nice. A note once in awhile to say thanks for watching the kid so we can hang out, a cup of coffee, offering to watch the pets while we are out of town. Certianly not required, but those are just functions of empathy and kindness. I AM doing something for my husband, but, really, also for her too.
Wives like me? Wives like me ask their husbands when the GF is moving because she has a business trip planned, but wants to be around so that my husband can help her move. That's az "bad" wife like me.
All that said, I don't think all these actions are maniacal. I think in some cases people DO use poly as a way to avoid intimacy. I see this in my H GF, i see it in myself! To consider the act ions of others and be empathetic, some times takes a lot a self-security that many people don't have. But, as I said before, I aim to learn how to be selfish!