I'm going to try and answer what I think are the questions you are laying out. Poly is different for a lot of people. However, I don't think you should put a label on poly people just because of the particular person you have run into. I have seen this before.
"I'm dating A and they are poly but a douchebag so poly people are douchebags!"
Um no. It's like a Venn diagram. There are douchebags and there are poly people. There is over lap. However, being a douchebag does not make you poly and being poly does not make you a douchebag. In other words, a person's douchebaggery transcends their relationship status, sexuality, sex, race, religion and all that. It stands on it's own!
For some people, they may 'do poly' in a way that has more relationships with less connection. It doesn't mean there is NO connection, just that they aren't looking for something so all encompassing emotionally. For others, they like fewer relationships that are more emotionally connected. Neither is right or wrong. Some people go looking for relationships, some let them find them.
As for using poly to hide? Well, just don't see that working long term. I am pretty comfortable in saying if you read enough on these forums you will find most people here realize that it's harder to hide your issues or not deal with them. In one relationship, you can kind of do that, not healthy but it's often doable. The more relationships there are, the harder it is to hide your issues. I know many of us have to deal with the yucky emotions. Not just, "I'm jealous it sucks you stop!" But a whole internal monologue of why am I jealous? What about it makes me feel this way? What is my trigger, now how do I deal with it? What am I not understanding or getting mentally but not yet in my heart?
Rarely will you see someone come here upset about something and see the advice, "Well tell them to stop then!" More likely than not you will get questioned on how and why you feel a certain way and how to communicate it to work it out.
TL;;DR Sorry if your honey is being douchey, but it's not the poly, it's the person.
Me: Late 30s pansexual poly.
DH: My husband of 19 yrs and father of 3 teen girls.
DC: LDR of +4 year