Clarissa, you have asked a bonafide sociologist and an anthropologist, and for some reason you’ve also asked me.
Sven Williams and Heinrich Müller have both advanced convincing and complementary accounts. Clearly, there are many social factors playing a role here, and there is room for more than one explanation.
The factors I’ll point to are on the Western side only, as I am not familiar with what happens in the East. I think they are contrary to the factors Heinrich identified, but like I said, there’s lots of stuff going on.
One narrative that prejudices Westerners against plastic surgery is the ideal of the natural beauty, and related to it the notion of authenticity as desirable. This is a fashion, as all ideals of Beauty are, but it is one that is on the ascendancy, as a reaction to past and present excesses. In fact the desirability of plastic boobs and of natural boobs is a competition happening in Western culture right now.
The reaction against silicone, ducklips, Botox and so on is partly just a swing of the pendulum, a reaction. Plastic surgery aims towards the current beauty ideal, and often overshoots past that ideal, to the derision of those who uphold that ideal. (Women more often than men, I suspect.) Partly, it is just a competing narrative of naturalness and unaffectedness and anti-consumerism, which of course can itself be just as consumerist a narrative.
The other social factor, which I think complements Sven’s explanation, and indirectly Heinrich’s, is that of vanity and frugality. To spend a lot of money on yourself looking good is condemned by many traditions within the West as wasteful and elitist. That narrative may not be dominant in Orange County, but Orange County is not the only cultural broadcaster in the West. The association of beauty enhancement with surgical procedures, which are dangerous and inaccessible to the masses, enhances any such anti-elitist condemnation.