Unless you're on the business end of things and most of your new customers come from search engines - in which case optimizing your site, which offers the products people are actually searching for, to the top of the list (and aren't cheating with giant link-farms....). Good SEO has a lower CPA than just about any other kind of marketing.
Now, if we're talking about SEO where people are link-farming to spam pages just to get ad-hits and get ad revenue and other spammy behavior of no real value to anyone but the person doing the SEO.....i'm all for hte new classification.
Now, if we're talking about SEO where people are link-farming to spam pages just to get ad-hits and get ad revenue and other spammy behavior of no real value to anyone but the person doing the SEO.....i'm all for hte new classification.