Just an update real quick. I did email ZPizza about my experience yesterday... They have already responded and stated they would be speaking to the manager at the Scottsdale store about my experience & about the rude delivery driver. I was also asked for my mailing address for some certificates to make up for the service, which I told him I'd be more than happy to use... As long as I can use them at a different location.
I have to admit that made me a lot less angry about the whole situation because they didn't have to do that... So that DOES say something for the company in that they actually care about customers being happy enough to return for them. I thanked him and told him that their pizza really is the best. Bumped it up a star (for this location) due to the company being sympathetic to my disappointing evening.