I think the "just as easily" is highly debatable. I'm not a container evangelist by any stretch, but if you were going to take a "just chroot it" approach, the very first thing you'd want to do to ease the operational burden is define some kind of standard app packaging format that defines what's in the chroot and an entry point and an environment, and maybe some scheme for mapping external data and various other niceties you get with containers, and at that point, congratulations, you've reinvented containers.