Because if you are contesting an event at match play, you don't need one. When you think about it in a head-to-head context, any course is fine for match play, and it doesn't matter much if any particular hole is twenty yards longer or shorter.
Technically any course could be OK for match play.
But, is'nt the whole point of match play not to bring different strategies into play then that of stroke play?
In this case shouldn't courses be played, and designed differently for match play.
A match play course should have more risk reward holes then a regular course made for stroke play.
It should have weirder greens, crazier pin positions, more driveable holes, more shortish par-5's, etc.
I think if there was a RC doctor it would make the RC more interesting...