I use MailChimp to send out my company's email newsletters. We have Google Analytics integrated so that we can measure performance. When MailChimp sends out an email, it will attach the various utm_ paramaters to all of our links. This includes links to Facebook, Twitter, YouTube, LinkedIn, Google Play, Apple.com and more. Is there any benefits to this? The links go straight to these other domains and do not pass through our site. So what exactly is getting tracked here? Nothing, right?

I'm wondering if there's something I'm missing, or if MailChimp is just applying utm_'s to every link instead of being smarter about it and only linking to domains that belong to me.