Really? I think it has huge potential eventually if it's priced well and isn't marketed like a gimmick or just for gaming or something. There are very few limitations to the value of this technology over time if well implemented.Expensive gimmick. Outside of field service as a business application (which Microsoft do a good job of) I can’t see any practical application.
Use it on museum tours. Instantly view information about a creator without having to look at your phone. Want to see other work by the same person? Sure. Side by side? You got it. Want to compare a different artist? Sure thing. Maybe you'd like to see the art you're looking at as it was originally displayed when it was created. You can do that too.
Same thing for an archaeological site. Built right, you could view crumbling ruins with an overlay of how they'd have originally appeared - and be able to walk around in them. Or as a tool for modern archaeologists to revisit a dig layer by layer. That could be invaluable to the (inherently destructive) science.
Remodeling your home? Walk around and preview your changes in real time, exactly as they'd appear when completed. Don't like what you see? Change it. Want to buy or build a house? Take a walkthrough without having to travel to it or have it built first.
Use it to make your computer monitor as large or as small as you want for whatever you're doing.
More medical and mental health treatments may be adaptable to the technology (some ar/vr is already used in the medical field, but there's room for expansion). Give a hospital bound person the ability to attend a family function almost as if they were actually there.
Sit in on lectures and labs with top experts in whatever field you want to learn about without the inherent depersonalization of staring at a fixed screen.
Far more realistic technical & engineering training opportunities, the ability to "travel" anywhere in the world and engage in any activity instantly, fitness and sports training, sculpt, re-engineer a part of a machine virtually, situate your product in a home or business. Preview a hike on an unfamiliar trail. Visit and walk around a destination before you arrive. Pick which beach you like best before you go on vacation - by virtually standing on it and taking a look around.
Some of this can already be done in an extremely limited manner on the flat screen of a computer or phone, ar/vr glasses have the potential to take that to a new level. Other things simply can't be replicated on a "flat" device or are extremely awkward or dangerous in ways the ar/vr glasses could help resolve.