I'm an active member of our local PMI chapter, and have heard seminar presentations from everything from zoo managers, to city managers, to a PM for a virtual border fence project. What that has shown me is, if you can master all the areas to manage a project, you can run your own business, team, department, city, division... etc. It teaches attention to detail, focus on scope, time, budget, risk... you can even apply the PM principles in daily life.
Broader PM education is definitely a good idea.
My org is doing more... and we need to teach the folks who have been doing projects for years the actual correct methodologies (self included), as many of us have just been doing it by default and drive.