and i thought that social media links were at the bottom of the food chain
Yeah, that's a misconception that's common in technical SEO. And that's why I only came around to it slowly.
It's not the link itself that does the trick, although lots of retweets, etc, might be helpful. Instead it's the conversation itself that can spread and that attracts wider interest in your content. That entire process can spawn natural backlinks from others who are looking for interesting things to write about. It's "word of mouth" marketing, done digitally.
Especially once you've got a following, people who search social media for content in their areas of interest will see what you're offering - if you share it well.