Yes, you're right. I currently don't have any other idea how to deal with those small, spammy SEO businesses than to raise awareness about the subject and hit their customers directly. It's sad, because the customers here are usually not to blame - like you said, they neither know nor understand what's going on here. I was quite (pleasantly) surprised by the immediate reaction of that particular person, who 'out of respect for my space in the Internet' decided to take action that cost her money. I deeply respect such people. "Vote with your dollars" mindset should be encouraged, IMO.
Anyway, here's the story - it's in polish, but maybe HN folks from Poland will find it interesting (and get to know about one thoughtful photographer) - http://temporal.pr0.pl/devblog/2011/09/19/spam-seo-i-fotogra....
Back in the time when I was too lazy to install Akismet and manually managed comments on my blog (via moderation), I used to see from time to time annoying SEO comments - a fake profile with genuine-sounding comment, backlinking to a website catalog. When I was especially bored, I used to go to such catalog in order to find the SEO company who was spamming me.
On one occasion I contacted a private photo studio, asking if they're using SEO company XYZ, as links to them are all over the catalog. It turned out that they just hired a SEO company to 'position their website', without knowing anything about how it's done. I explained the situation (sending screenshots), and the studio immediately ditched the SEO company and hired another one. I was amazed by this attitude and featured a special advert-like post on my blog for them and we're in good contact since then.