Sounds funny, but your theory is false. I use GMaps every day to drive to and from work, with a very simple route that's almost all on an interstate highway. Almost every day, it gives me the exact same route (which is so simple I really don't need GPS navigation at all for it). Sometimes, it gives me a different route because of an accident, traffic jam, construction delay, etc., which is why I use GPS all the time, but I see absolutely nothing to indicate that Google intentionally makes my route more complicated than it needs to be. (And yes, these delays are real: this road is under a lot of construction at the moment, and it frequently has crashes and traffic jams in places.)