If one is a film star, fashion model, glamour model, porn star, prostitute or lap dancer then the body is a tool - a means to making a living. The girls in these industries are competing against each other for work so cosmetic enhancements are all just a part maximizing their chances of getting contracts or work.
I wonder whether people outside these industries are looking in and getting the incorrect message that such things are normal and desirable in real life?
But is it the "incorrect message"? People have been getting tattoos, piercings and so on for centuries. Is breast surgery really much different? It's still modifying your appearance to please yourself and/or other people.
By the way, I'd just like to point out that I'm not a "fan" of fake boobs, just that I can see the reasons girls would do it. Each to their own and all that.