I agree that using free (libre) tools is preferable, but a lot of this facilitates that. For instance, you can deploy a GNU/Linux image using the DigitalOcean credit and gain experience deploying on a LAMP/LEMP stack and doing things like creating iptables rules and things like that, which is good real-world experience that is in no way temporary or platform dependent.

Git itself (as I'm sure you know) is a free tool, and learning git is a worthwhile skill no matter where you are using it. Hell, I know people who use git for collaborative document management.

And the SSL stuff and domains offered through namecheap are going to be helpful to anyone who wants to go into web development. Knowing how to set up a domain, with proper DNS records and SSL configurations, is a pretty basic task for people who do web stuff. And, again, these things are platform agnostic. I think there is a lot of value offered here, and not all of it serves the purpose of furthering vendor lock-in.