Q: I'm naturally well endowed and think anyone wanting to be as big as (or bigger than) me is crazy for wanting to do so.

A: "The grass is always greener," etc. Seriously, you may have had past experiences which have created a negative association with large breasts. There's a pretty good chance that the women contemplating this have never had to deal with those, such as sprouting big boobs during the early years and having to deal with the negative reactions of family or schoolmates.  That said, the women who do go down this path either end up pleased with having done so, thus meeting their expectations, or discover they would like to go bigger still, thus reinforcing the prior decision to go bigger.