^I have been thinking about this very subject. Boob envy often leads to bigger boobs, but not always boobie greed; often a girl is satisfied with her size. Of course, this may change if a friend has even bigger boobs, then boob envy returns. But boobie greed has, in my humble opinion, certain earmarks. Despite her size, the boobie greed girl always wants to be even bigger. And the boobie greed girl has a relationship with her boobs; she loves the way they look, she likes looking at them, often even stroking them when bored, she likes how they obstruct normal movements, she likes how heavy they feel and enjoys the jiggling and sway when walking. The boobie greed girl actually thinks about her boobs very often, multiple times an hour if her attention is not focused on something. And the boobie greed girl knows her boobs are huge, yet she still want more; there is no body dsymorphic syndrome here.
I think half of the girls out there have some degree of boob envy, but very few actually have boobie greed, because most have a ideal size in mind. The boobie greed girls are very rare and they have no particular size in mind, only bigger. If only there was a means of making it possible for all, we would see those that truly have boobie greed.