Of course there are harmful SEOs, ones who play the system with malicious intent. However consider that there are malicious marketers, malicious politicians, and malicious forms of every other occupation. The government does not regulate [all of] these.

At some point the government has to let the people govern themselves rather than coddling and protecting them from themselves. Protecting from themselves leads to an unhealthy government / citizen relationship.

[Edited to clarify text, added text in []s]