"Charles Brabham" writes:
Why? - My explanation for this is that the same amateurs who tend to be
interested in WIFI also tend to disparage the idea of established amateur
radio digital networking. - They all appear to believe that we would be a
lot better off to just use the Internet instead of building independent
amateur radio infrastructure. - So they don't do it.

It could also be that they're more interested in low-speed DX networks
than local wifi-like networks. Wifi works perfectly well on part 15
with no licenses needed. Why bother with a licensed version of the
same thing? And how do you re-tune the wifi cards to ham bands anyway?