Awesome response!
I think even the Walmart guy changing his own oil is a questionable case for a full synthetic. Again, all the arguments pro-synthetic encourage this guy to go 10k+ miles, perhaps much more, on his changes, which is not good for the engine, even if the oil can take it. It may void his warranty, and we can only hope the guy will recycle responsibly instead of being lazy. If it's an older car past warranty, then switching to synthetic is a decidedly dumb false benefit.
Unless the engine is broken in on synthetic and has very tight tolerances, such as a racing application, switching to synthetic even in our proud Genesis is, pardon the pun, snake oil. You can get a better mileage increase by simply using premium gas and keeping fresh oil in the engine using the regular intervals - I wonder how many people bragging about their synthetic oil turn around and pump cheapo gas (and claim gas doesn't matter), never change their filters, run low tires, and so on. The whole synthetic deal is an easy way to excuse bad habits in consumers for something that is unnecessary and questionable. I once ran Mobil synthetic in a sport motorcycle and all it did was get me burned out valves, eventually.
All branded oils today are so good, they can all go 10k miles, so it's just not the issue it was long ago, but the marketing claims still push the same fear-mongering. All you have to do is change your oil with virtually any major brand within 3-4k miles and the engine will be happy. Doing it through the dealer, as long as they're not overcharging, is also very wise for long-term care. Otherwise, Grease Monkey and other quick services are a great way to go (just don't fall for the add-on costs) since they do all the recycling and check a few other things while you're there.