He's just making the point that it's unethical, which it is. Even if it boils down to simple bandwidth theft.
Even calling this "bandwidth theft" is quite the hyperbole—if the server can't handle the bandwidth, then rate limit the requests.
I think if you're serving out pages to the public, you don't really get to tell me what kind of browser I'm allowed to download it with. As long as I'm speaking HTTP, it seems fair.
Sadly, that law has been slowly creeping against this mentality... Lately I feel like I'm some old internet hippy with these views. On a site called "Hacker News", no less.
I guess it's because everyday more and more people on here are finding themselves on the other side of the fence, i.e. finding that some of their users are ripping off their content/site.
Sell a product or service.