I was writing a contact in the marketing world and I realized why I do not want to do market research for some types of companies, and why I prefer to work in the social media world.
I do not want to work at a research firm where I would have to do research for a fast food company, a tobacco company, or a soda company. I think one important aspect of good marketing, and good understanding of the market, is to make a good product that fits consumer need. This does not mean you make products that manipulate people's brains on a chemical level (fats, sugars, nicotine, empty calories) . Good design is important to me, products that harm people's health are defective by design and I do not tolerate treating people like that.
One reason I like social media is because it can make people's lives better, and it needs to be designed well to do that.
Good design makes life better. Some products are designed to enrich some at the cost of others, but are marketed in quite a different way. For more on fast food, read Eric Schlosser's Fast Food Nation.