They are are still that expensive because they all got crossed with carpet pythons (if I remember right) and they can't get anymore for legal reasons. That could be another great species for the hobby but now it isn't because most are gone/so crossed with others you can tell it isn't a diamond python.
I'm not sure if the initial population we had in the US was enough to sustain a pure population in the long run. But it is an example I'm using.