This is something I’ve wondered about previously… I have no idea what the optimal dev scenario is for roots, but for me personally I was looking to run staging and production on one server, which at least cuts the number of servers you run in half - I got some great advice from @fullyint here:
Staging and Production on same VPS
What I’m enjoying is that there is a theme, WP environment and full dev/provisioning environment all built under the same principles. On some sites I use Sage, on some sites I use Bedrock and eventually I’ll be using Trellis in a dev/production environment (still building up my courage).