There are already demos of this:
https://www.youtube.com/watch?v=JnkMyfQ5YfY
...but drones use so much power that it's unsustainable beyond demos. Beaming power to them suddenly makes this useful because you can keep them flying indefinitely.
I'll predict that if Disney actually have this working beyond a prototype, we'll see demos of drone swarms building complex objects out of children's bricks within a year, and prototypes of tool-wielding drones actually doing assembly within another.
+ A small sphere drone with a dusting cloth around it to vacuum things.
+ Never charge a remote control anymore.
+ Knowing if someone is present by sensors in the floor, furniture, etc.
+ Automated valves on the heaters.
+ Charging locks (not requiring wires should be better w.r.t. security).
+ Easier light placements. They can be put in any cabinet (where it is normally dark, but you don't want to put wires).
+ Blinds, curtains control
+ Speakers integrated in couches / chairs. Perfectly located. Vibrations etc. is also cool as experience.
+ Clothing. So called smart "shoes", "belts", "umbrellas", etc. only hinges on wireless charging taking off.
So this could totally be used for a HMD already. I wonder if it interferes at all with data transmission protocols that are used for wireless on the currently available HMDs...