Where would they get the money? From cutting out the middleman, from increasing sales by offering an alternative to the terrible dealership experience (spending 1-2 hours buying a car is not ok) and from gaining the flexibility to offer alternative business models (i.e. subscription models).
Dealerships are the past. They may very well be the deadweight that will cause incumbent OEMs to sink rather than swim.
The legacy manufacturers could absolutely copy this approach and would love to do so.
Traditional car dealerships need someplace to store all the new and used cars which quickly gets into hundreds of cars sitting around. Showrooms on the other hand can get away with representative samples which requires vastly less space. That means they can afford locations with vastly higher costs per square foot.
This discussion is about American auto dealerships.
They would want to cut out the middlemen car dealerships.
Both Ford and GM have substantially lower WACC than Tesla. The figures are public.