I am not only aware of packaging's influence on sales, I am a a participant in the phenomenon. I like convenience, and I've made purchases where the container competed with the contents for primacy.

So perhaps I ought to understand the foofaraw over Diet Pepsi's new thin can, which it introduced at what someone decided was Fashion Week. My hometown newspaper editorialized against it, and my Twitter universe has been bubbling about it as well. But to me, it's just a can.

Lynn Grefe, president and CEO of the National Eating Disorders Association, says in a Wall Street Journal blog post that she's not bothered by the shape but by the marketing initiative that goes with it: 

The campaign celebrates being skinny and suggests that strong, confident women must be so. That the Skinny Can campaign is being paired with Fashion Week, an event put on by an industry that has had to address eating disorders among its model ranks, is particularly problematic, says Grefe. 
This campaign won’t cause anyone to develop an eating disorder, but could trigger someone who is already vulnerable to negative body-image issues to start dieting or become more extreme in their dieting, which could eventually lead to disordered eating, says Grefe.

Grefe is the real deal, so if she says it, I listen. But I still feel that, compared to the chemicals inside the can and the sum of all marketing's ills, the attention on this new can's proportions is way out of proportion.