I'd also like to add that having a month dedicated to it and pink things all over is awareness but it also serves as a reminder for people to get checked for it. If wearing pink helps some people to take the time out of their busy life to get checked, it could save their life and doesn't that make it worthwhile?
Also a lot of the money from the sale of these items goes to research to help fight cancer. (I know as others have said that not every place that you buy from does that but many do. Do your due diligence and buy from places that forward that money on)