The claim wasn't that he committed plagiarism, it was that he lazily "repackaged" a blog post: http://cafehayek.com/2016/02/40405.html

It's not plagiarism, but it's also not something a moderately talented high-schooler couldn't have done. I mean he even used the same food examples, the same real-estate examples, the same travel examples, the same home appliance examples...all he did is add some BLS stats.