"anything you need is a phone call and a FedEx overnight delivery away"
Only in the US. And even there you may have some major inconvenience. Let's say you have a cell phone and your hub brakes down in the middle of nowhere. What address do send parts to. The reality is that if there is the slightest chance of that happening you will have saved a lot of money just getting the better parts in the first place.
When sealed hubs were first introduced the idea was mostly that they would survive more mudplay. Then it used to be said they would survive longer between "repacking". When it comes to normal road touring. You should get a few K out of your hubs before they need repacking. I have cycled a week of rain and opened LXs and they seemed a little wet, but the grease was still intact, it hadn't washed out. And the only reason I had opened it was maintenance after a 2 week tour. If I had Phils, I probably wouldn't have even bothered to look. Bearing wise you can do roadside maintenance, as long as you have grease. The bearings aren't going to wear out and break most of the time, and they are stronger in a packed wheel than a cartridge wheel because they are bigger balls.
The main things I worry about, and I really haven't had any reason to worry, are broken axles, and torn out spokes. Not even the expensive billet hubs are mostly better on torn out spokes, they tend to billet aligned with the axle. Mostly the spokes should be fine, but there are some lacings with high tension and dish on narrow width hubs (That I don't use) that can add to the stress a bit. Broken axles could be solved for a few bucks with hardened axles.