Your users and customers do, even if they don't know it. A 3-year Fortune-500 study conducted by research firm Peer Insight found that companies focused on customer-experience design outperformed the S&P 500 by 10-to-1.
I do. I'm a freak about it. I love integrated marketing and GUI design, I can't get enough of usability and SEO. Organizing information, so that it is easily found and then absorbed in a compelling way, is my passion.