Huh?

I don't understand. In the past I had a problem with spam on this blog so I initiated (at the suggestion of a reader) the use of those swirly letters you have to type in to gain access to comment. This eliminated it mostly, but every once in a while a person (because I'm assuming it has to be a person to get past the swirly letters) will leave a spam post...usually trying to sell something. Today I received one such spam-comment, it was on this recent post regarding tall bikes (you can take a look for yourself). I've never spammed a blog before but I'll just say this...if I were going to spam a blog that mostly focused on bicycles, cooking, and the spiritual side of life, I wouldn't try to sell large truck parts on it. So I say again...huh?