Sorry to hear about your experience. I still haven't gone diving with IDH but know a few of the staff there.
There is a large division between local divers/club divers and the tourist divers. As ChOppersrule said, if you paid the tourist price, there should be service included. I ran a dive shop in Guam for a while and we always carried the tanks and gear. It is something that you pay for. Now on the other hand, if the gear and tanks are the guests, I would ask them if it was okay to carry their stuff for them. The key is communication.
A general rule of life, 'treat others the same way you wished to be treated.' I've got all my own gear but when I'm on vacation, please carry it, but I will set it up.
It definately sounds like you had a new DM/Instructor who needs more experience in the business to understand. In fact, if you tell Matt, I'm sure it would be a learning experience for the new instructor, thus he won't make the mistake again.
As far as the urinal on wheels, wow. I have no comment. kusai! When I worked at a different dive shop in Guam, we had a rusted out Previa van. The windshield wipers didn't work and the back hatch didn't close. We had to rope it down! But, it didn't smell like urine.
The one thing I've learned is that IDH caters a lot to the locals and military. Mainland divers seem to appreciate it more. The other shops that advertise to tourists in the discount booklets cater specifically to resort divers who dive a few times a year when they travel.
Any hoo, my two cents given. As a local, living in Hawai'i, I apologize for your bad experience and hope you come back and dive again.
Chris