The problem is that there is a lot of of variance in preferences. Clothing etailers have the same problem where some people are used to it being snugger in different areas. Folks who share dimensions may be used to different fits.
It's common to shape the sole of performance cycling shoes, but not by way of scanning. I had a pair done a while back which where made by me stepping on a heated rubbery platform that slowly took the shape of my feet. The thing I stood on was then used to vacuum-shape a carbon fibre insole.
I've had this done with some custom birkenstocks before. They heat molded the cork insoles to fit my feet. They were very comfortable and well worth the money and time saved from not having to break them in.
Hockey shops are 3d scanning feet, but they don't have individualized boots to go with that; it just gets you a shoe size and one of three fit profiles within that size.
Better ski touring (and even just alpine skiing) boots have inner soft parts that are heat-moldable to fit perfectly to everyone's unique feet. Ski shops all have these heat machine specifically for this, but there are tutorials on how to even do it at home with just rice, socks and microwave in case you shop online (with almost no risk of destroying it as usual)