I think you are just thinking about this far too closed mindedly. Automation means more than just going out and spamming dodgy blog networks. It might be that your automation is things like finding contact details for 1000's of websites. Or perhaps discovering the quality of the site by automatically grabbing the backlink information. And as cc976a has suggested, you could also use automation to find 100 blog posts that talk about repairing boilers, and then use some other automation to narrow down your "hit list".
There's lots of scope beyond what you will have read on blackhat forums.