I think it is time to divide SEO into two parts. One part where you optimise your site, you change ugly long urls to prettier easier to understand. Decrease the loading time and think about how and what you write. And similar things that mostly increases the experience for the users.

And then the other part where you buy links and other crap.

SEO has started to become asociated with evil. It can be, and it is often easier to do it the evil way. But to some extent it can be done in a good way. You can give customers an awesome experience so they blog about it. Give away free stuff and so on. Its not only evil.

Most people call this "black hat SEO" and "white hat SEO." As with most things, it's not quite so binary a situation.

Even so, breaking it into white and black hat ignores the likely larger problem of ignorant SEOs - those who think they know what they're doing but are completely worthless. In my experience, most SEOs who take "black hat" tactics tell their clients. It's the ignorant SEOs that waste the time and money of legitimate businesses and earn a bad reputation for the industry.