Software, by and large, does not make people happy or do what they want nearly as reliably as steak does, and so if I were them I would be much more finicky about paying people to make it for me than I am about paying people to make me steak.
And especially, software made to order has even lower mean and even higher variance than most of the software that people use. And you don't know what you're getting until you get it, at which point the incompetent software vendor is demanding some ridiculously exorbitant sum for something it turned out you didn't want anyway.
You personally may not suck at programming, but the majority of programmers do, and so people are very justifiably unwilling to cough up the dough programmers demand.