Some of these are literally debatable. Some are indisputable. Please share your thoughts. :)
The reason some agencies do this is because it brings results, as there is a small but measurable conversion rate. In my opinion I think this is a way to burn bridges, create bad will and set it up to have that kind of outreach increasingly ignored. Well, it already is ignored, which is why these kinds of campaigns are scaled up, like those of all email spammers. The actual conversion rate of knocking down the door type outreach is low.
Publishing your actual outreach template in an SEO article
Being transparent makes some people feel good about what they do because they can confidently say they have nothing to hide. However, publishing search strategy specifics in public has been known to cause a response from Google.
Outsourcing the entire strategy in the dark
One thing many publishers who have come to me for help is that they had outsourced their entire link strategy to a company that did not reveal exactly how they would obtain links. The best way to outsource is to do it as a partnership.
Forum & Comment Spamming
This is one of those kitchen table strategies small business newbs tend to get. To them it's "spreading the word" but to publishers it's spam.