"About half" of Reality Labs spend is in AR R&D according to Bosworth. I'll be very interested to see what Apple brings to the table, but would not expect Meta to be playing catch up.
It would appear as though they are, at least according to this article from 2015. One would imagine they wouldn't continue expanding once the $/sqft leveled off:
"$3,785 in sales per square foot, a figure that would put Warby Parker behind only Apple in terms of retail efficiency. Though those numbers have dipped somewhat as Warby Parker has grown, the company is still averaging about $3,000 per square foot of retail space, a figure that’s in the same breath as Tiffany’s estimated $3,043."
There is a new D2C company out there called Hubble. They don't offer custom base curve or correction for astigmatism, but I was able to get one year's worth for $265.