Well I went back and read through this entire thread again partly because this is a very interesting question and also to track the various twists and turns of the "conversation" so far. From this I have come to 5 conclusions;
THE BASIC QUESTION
1) Your typical big breasted woman does NOT lead a charmed life because of their breast size.
THE EXCEPTIONS
2) Referencing those few exception examples, e.g. "Pam Andersons", actually reinforces the fact that the TYPICAL woman does NOT lead a charmed life from larger breasts. Nearly all women are not this type of exception - porn start, bimbo actor, boob model, etc.
ATTENTION
3) Attention does NOT equal a charmed life. A charmed life is categorically positive. Attention can range from very positive to very negative attention. We can say that 50% of big boob attention could be classified as negative in some way.
SELECTION VS GENETICS (choice vs. nature)
4) Women who choose to enlarge or emphasize their chests by whatever means do so as a decision based on external motivations. They have a personal reason for them being that size. Natural women did not have that option. They grew naturally and had no say in the matter. That makes for a big difference in how they relate to their own chest.
Whereas the enhancers have done so specifically, almost selecting a size, typically change as adults and can rationalize some immediate personal gain the naturally large busted had no say in the size, rate of growth, age they are when it happens and can have surprisingly negative lasting effects of this process. Most large chested women are naturals.
BIOLOGY
5) Biologically speaking enlarged breasts on women are a secondary sexual characteristic that signifies sexual maturity, health and to a lesser extent fecundity. They are an evolutionary result of humans strong group structures, prolonged infant developmental stage, and need for reinforcing mate bonding. Additional attributes assigned to them come from societal tags, emotional association and popular stereotypes. Collectively all these factors combine to give these protuberant fat filled mammary glands much greater significance than one would expect - however they do not guarantee a charmed life.
Also, I will say it again:
Attention does NOT equal a charmed life.
The majority of women who lead charmed lives do so in spite of their large chests.