Yeah, but isn't that the point? Sure, you're not going to let these companies dictate what you do but it's pretty much impossible not to be swayed at some level. Where do you draw the line?
I remember watching on Frontline (yes, I watch PBS, I'll admit it) that drug companies spend 14% of their operating budget on advertising. This is the same amount they spend on R&D. (Ok, to be fair, there is a lot of debate about the actual numbers because these companies are not compelled to break down advertising costs.)