This stuff is all fine and good for a few VMs. I wouldn't try to run a serious endeavor using them, unless I really wanted to spend a bunch of time diagnosing, debugging, and sweating.

The reason automation, CM, and devops have taken hold is because people are so goddamned tired of serving technology like it's some kind of god to which we owe worship. Screw that. I want the VMs to go make ME a sammich, not the other way around. Trying to build serious infrastructure using nothing but shell scripts is a quick trip to the temple of server-worship.