Travis,
Usually in such cases the maintenance company (at least a reputable one) will over see all aspects of husbandry and fish selection. Its in their best interest to do so, if they didn't do this the costs would be overwelming and the account would be lost. I would dare to say that the fish in these exravagant accounts are better taken care of than most. Having such a huge tank helps in their health and combatability. Now saying this, the people who have the money for these tanks and don't have professionals maintain it are in for trouble but this rarely happens. If you have enough money to build it, you are sure to be able to afford the neccessary quality service.
If we are to have greater postive effect for our hobby and the overall marine environment we have to get non hobbiests to appreciate the animals and ecosystems that they normally wouldn't know about. The aquariums provided for these people who in the past wouldn't want to have one due to maintenance, now have a better appreciation for the environment they come from. This and public aquariums are a great way to get a larger segment of the population to appreciate and care about the reefs and the oceans in general.
"If you don't know, you don't care. If you don't care, you don't protect."
Gary
Gary