Hidden costs of open source

Upon reading Hidden costs of open source one starts wondering as to what are the 'hidden costs' the article insinuates? The author suggests that the cost associated with learning how to use (install, maintain, and run) a particular software is a hidden cost.

"There we are. Cost again. If it's so easy to use and it is reliable (one assumes it's reliable since apparently Nasa is using it to run mission critical applications, although that would put me off becoming an astronaut), why am I asked to shell out $1,500 for entry-level support? And support costs can go as high as $62,400 - hardly a cheap option."

But this is nothing new with either commercial packages or open source software. Using any software that is complicated requires learning and maintaining, independently if it is closed or open source. The expense of learning and maintenance hardly classifies as 'hidden cost'. And guess what, you don't have to by the support from the actual developers of the open source. You can learn it on your own and do it yourself, or hire other competitive training and support consultants. Sometimes you wonder why this article is even published as a serious discussion point. Hmm…