The over all concept is occupancy. You won't have 8,000 people inside the building like a rock concert with pyrotechnics or a sporting event. You will only have a staff, some actors and a limited occupancy inside at any given time as prescribed by the fire marshal, traditionally groups of 5 or 6 paced out.
You are implying you would only have to evacuate a hundred people in a few minutes rather than thousands that will never make it out. As a result the existing facilities are far less than even the original design of a store with so many bathrooms, so much burden on parking etc.
In short, how much is this going to cost the city to service things you have not provided for or what liability do they face if they allow it? Very little if any burden is your presentation.
In fact your electrical cost classification could lower and things like that if it was properly classified, which they won't hear of as it changes/lowers the tax appraisal the city gets from the property but, another thing that illustrates the property exceeded the requirements in comparison to how you manage your event.
Another fabulous post from the U.S.Department of Wild Imaginings, now in spectaclar stereo, sponsored by the Adhesives and Sealants Council, suggesting ways to stick things together since the 1800s. Not fabulous in a gay way. Your results may vary. Illinois residents add 8% sales tax. These posts have been made by professional post makers, do not try this type of posting on your own without extensive training, lovely assistants and a trusty clown horn.