With the Denon, you could use 2 of your surround channels for a Zone 2 yes, but can that channel play a different source at the same time as the main source? The Onkyo does. Even if it will, you are sacrificing one set of surround speaker outputs.
So yes, I do believe for multi-zone audio the Onkyo provides more provided it is hard wired.
All that said, I’m not sure the $150 would be worth it even with all things equal, I would save the money and get the Onkyo if I were the OP.