Most theaters I frequent typically have someone taking tickets, but they don't seem to usually care if you have outside food. I remember when I was younger we very brazenly brought in fast food to a local AMC, not trying to hide it, and nobody said a thing. But then that might depend on the employees. Seasonal hires seem like bigger sticklers for the rules in general, as evidenced by them not giving me rewards points while using my moviepass card, as opposed to someone in September literally charging me full price on Tuesday (instead of regular half price for people on the rewards program) so I got more points since moviepass covered the cost, so considering all that the enforcement may depend on time of year.