The expense is in its deficiencies, which include (in my perception) plentiful long-tail bugs and issues, lack of flexibility, and in some cases lack of maintenance, as a single author can leave their work for whatever personal reason.
I don't think it's particularly surprising that humans are better at things than robots, sometimes even purpose-built robots. The question is if robots are good enough that the difference doesn't really matter.
It's throwing shit in a box. Who cares how neat it is? As long as things arrive sealed and intact, it's fine.
How would you verify that your belief is correct?