First, does anyone doubt the value of learning Ruby is much greater than $2,800? I imagine the course is targeted at someone without any programming experience[1], which only increases its value.
Second, not everyone can teach themselves to code. It's an easy trap for us programmers to fall into, since we can often pick material up on our own. But we do call it "code" for a reason -- this is difficult stuff!
Third, many objections focus on the high price of the course. That's absurd -- it only establishes a higher value on the skillset those programmers already possess! We clamor for managers and sales people to just learn to program a little bit -- one way of conveying that value is to capture more of it in the training programs.
Fourth, these courses are just an option. Their existence doesn't threaten all the awesome free Rails courses out there.
It strikes me as a little bit of trademen unions. As if we want new programmers to pass the "self taught" trial by fire initiation ritual.
[1]I also understand the objection to the forum in which this course was offered; however, the primary objections in the article seemed to be focused on the cost of the course, rather than the manner in which it was advertised.
(edit, formatting)