It's not even REAL HD radio. It's just given that name because it sounds more appealing and in the beginning, HD meant Hybrid Radio.
Pedantically, it is REAL HD radio, because the term "HD Radio" is a catchphrase that was coined by Ibiquity, and therefore its definition is whatever Ibiquity wants it to be. It is Ibiquity's preference for the common name to be used in reference to their implementation of broadcasting digital content in the same radio spectrum as terrestrial analog FM and AM radio stations.
You'd be correct, though, in saying that it's not really "High Definition Radio" because that has never been part of the definition that's been applied to the trademark.
On the other hand, if an HD-equipped radio station shut off its analog carrier entirely, and dedicated its entire frequency allotment to its digital signal, then there would probably be more than enough bandwidth to carry better than CD-quality audio. But in doing so they'd cut themselves off from the majority of currently deployed, analog radio receivers.
The channels are commercial free for now but I bet that's just to get more people into it and then the ads will come.
I was under the impression that the main content of an HD Radio station's digital stream was typically identical to its traditional analog signal, thus subject to whatever commercial content might be on the analog signal.
But some stations may offer alternative content in one or more of their optional multicast channels. Maybe some of them they might be choosing to offer the multicast channels commercial-free at the moment - or perhaps, they might be having trouble attracting advertisers to pay for time on their multicast channels at the moment due to potentially low consumer uptake of HD receivers...