Parents punished by popcorn profiteering

It wasn't the terrible lip syncing that left a bad taste in my mouth at the Brisbane performance of Disney's High School Musical on Ice - it was the popcorn.
True a bucket of fat smothered in salt is always prone to a bitter after taste but this time it wasn't the artery-hardening properties of the snack that did the damage as much as the blatant rip-off of the product not to mention the anti-competitive behaviour of its retailers.
If ever there was an example of the profits being in the packaging it has to be Disney popcorn. A small box cost $6, the bucket a massive $13.
While it could be argued that if people want to pay for over-priced popcorn that's their problem, there is a much bigger issue here.
The regular food outlets at the Boondall Entertainment Centre normally retail popcorn for $4 or $6.50 BUT they are forbidden from selling it when the Disney machine comes to town.
Surely creating a popcorn monopoly and forcing patrons to buy the snack at the inflated special Disney price is in breach of some restriction of trade regulation - or if it isn't it should be.
The current popcorn piracy is too hard to stomach.