When my shell scripts become untenable I happily hire someone who is an expert at installing packages on a cluster of machines.
It's a complex problem and CMs so far are complex enough that I'm put off by how dense the CM language is. Every time I come across chef my ears start leaking precious brain fluid. Recipes, cookbooks, knives, bags, dependencies, acronyms I haven't bothered googling for... there's enough there that someone can dedicate their time to mastering it and be paid a decent salary.
No thanks, I'm already spending enough time as it is being an expert in something else. I'll just stick with shell scripts because at least I can understand those without much effort. If they become a problem I'll hire someone to fix it. :)
update: That was a little rant-y... after reading this article I might try Ansible if I get the chance. The problem I have with CMs is that they tend to be very complex because they solve a complex problem. Shell scripts tend to be simple (but crude by virtue). I am curious whether there is a middle-ground.