In most civilized western countries the dealer really can't recommend a power commander or similar device because it is formally illegal to modify anything that will change the emissions performance. Technically, when they do such modifications, it has to be with the realistic expectation that the bike is not going to be ridden on public roads, but will be used in competition or other closed track activities.
It is hard to pretend this when someone is running road tires rather than slicks or knobbies, but some dealers look the other way and enjoy the opportunity for a sale.
Jesse James, custom builder in CA was hit with a very large fine several years ago for doing this sort of stuff as a major business, and I believe that Harley has been bitten for cheating on this with the Screaming Eagle custom kits, many of which have been installed on bikes that were clearly heading out on public roads for the rest of their life.
So ... people will do what they want .... but it is getting harder and harder for dealers to recommend this sort of illegal modification. In this era when many automobiles get better gas mileage than many motorcycles, you can't make any arguments based on low fuel consumption for motorcycles either. I can get 50 mpg on the highway with my wife's Prius, and I rarely get more than 37 mpg on the highway with my R3T, for example.