[bshipp]

You're in their building, so I imagine your consent is stated as part of the ticket verbiage or in small print when you buy it. Regardless, closed-circuit cameras are pretty ubiquitous in private businesses, and have been for decades.

[mdp2021]

The idea of the poster was that customers are recorded during projection and that there is active real-time monitoring of said reception, e.g. to detect abuse.

So, "you are being watched as you watch". Not by an uncaring attendant, but by some actively processing automation.