It’s not reasonable for a LBS to keep a bunch of wheels in stock. Wheels are highly customizable and people get pretty picky about what they want. Plus, the quality of the build is really important and I personally won’t trust a run of the mill shop mechanic to build a wheel for me. I want a specialist who builds multiple wheels per week. Basically, I don’t think it’s in the best interest of either the LBS to sell or the customer to buy wheels unless they are super generic that can work on a variety of bikes for non-discriminating customers.
I know that if I ever taco a wheel, the LBS won’t be able to help me unfortunately, but I do keep a cheap spare wheelset in the garage so that I can at least still ride when I order my custom wheel online.