I feel like this is an uncommon fetish. Personally I regularly scour the site to satisfy my craving for that sweet sweet envy. I am super into humiliation, especially if the target of humiliation is powerless to change the source of the humiliation. This is especially strong with natural differences between people. I have the same thing with big and small penises. It's about 'natural superiority', having the qualities that are sexually desirable and shamelessly flaunting them, preferably in front of to those who don't. Many of you probably think it's pretty awful, and to be honest, it totally is, but I guess that's why it turns me on.
BTW, I have been working an erotic 'novel' with breast envy as the main theme. If anyone is interested I will gladly share.
Part of it's the contrast because diversity is cool, but also it gives perspective.
There was a moment in my youth when I had to consider that real people are not well endowed at all. I saw big tits drawn images and they didn't register as big but as regular.
I guess the humiliation observation is pretty valid. You shouldn't sweat liking that kind of thing. We can't help what we're into. What matters is what we do and who we affect.
There is something satisfying to me about women wanting/enjoying big breasts. There is a lot depressing talk about women who are not grateful for the situation. So it's nice.
Another part of it is that in the images with this tag, you better endowed girl seems to be trying to seduce the less endowed one. You can interpret her as just being vindictive but I see their malicious faces as being femdoms, pursuing the small breasted girl despite their big breasts and I'm like: good for you small breasted girl, you're going to get some.
I like all sizes though. Apples and oranges. Big has a prestige because they're rarer and there's just more to enjoy but like I said, one needs a point of contrast.