Pex pipe [1] might be a better choice than PVC because of its high pressure tolerance and the fact that it isn't brittle/prone to cracking. It does require nonstandard tools to work with though (ie. burly pipe cutters, special fittings, etc.)
But your point still stands. A master plumber might not be required for every part of every job today.
Thanks for the correction with regards to material.
I do tech/IT by day, but have a welding certification as well. Its extremely easy to braize copper tubing together for plumbing once you've practiced, but feels like its work that isn't necessary when there are easier ways to do it (ie the pex pipe you suggested).
Coincidently, I'm replacing two toilets in my home tonight. Wish me luck!
But your point still stands. A master plumber might not be required for every part of every job today.
[1] http://en.wikipedia.org/wiki/Cross-linked_polyethylene