I agree, there is no one strategy or tactic that works equally well for all. However, you have to take the approach that you need to market your web site in several different ways and see what brings the most ROI for you. For some, PPC is great, and that works well for them. For others, it's SEO, since they can create a lot of content on their site. But for others it's a combination of SEO, PPC, and social media.
You have to do everything and test---to see what works well for your site. Also, you cannot just do "one thing", like only directory submissions for SEO. You have to combine on-page SEO, creating content on your site, and some social media (social networking and social bookmarking) to do well in SEO nowadays.
The problem here is that far too many are quite naive re. marketing.
They think that any place where people congregate in large numbers is guaranteed to be an effective channel; i.e., that crowd size = success.
Depends on the food and the demographics of the crowd.
How well would pablum sell in a football stadium?