Don't forget judges hotels. Some share, some don't. Some locales require union labor for set up and take down. Not all meets are huge money makers.
So say $100 per gymnast
$2 - state/usag
$17 - judges
$2 - medals (top 50 percent, and the generally order a few extea, butbut be conservative here)
$15 - venue (going super cheap at 330 gymnasts and 5000 venue, which is doubtful)
$3 - coach/judges food (being conservative and saying 1000 for the weekend)
$2 - team trophies (assuming just medals for all around, since trophies for all around get expensive)
Plus insurance, gymnast gift and rental of equipment and all the incidentals. Do they have to rent linens for the tables? Back drops for behind bleachers if that's where vendors set up? What about backdrop for awards? Basically, without 700 athletes, I don't think gyms who host at an external site make money without a charge to view.
That $100 dwindles quickly.