I think it's more than this. Lots of people are willing to pay consultants $50k to build something for them. They are much less inclined to pay exactly the same price for the same product if it's pre-built and off-the-shelf.

People subconsciously feel that paying for someone's time is "fairer" than paying for something that's already built.

It may also be why aftersales and support contracts are so lucrative (in lots of industries).