My moral dilemma

I am, by default, a rule-follower except for one area of my life: movie theatre snacks. It is quite the splurge for us to go to the movies which we did today to see "Enchanted". (Very cute, by the way.) As we were getting ready to leave for the movie, we all were stashing our granola bars and soda cans in purses and I felt the small pang of conscience, wondering if I have been setting a bad example for my children. (Although since this has been our practice their entire lives, the damage, if any, is probably already done.) I could justify my rule-breaking with the fact that Zachary is allergic to popcorn and almost all candy bars or that I'm not supposed to have sugar, but my real reason is purely economic. Is it really fair to burden families with $3.75 sodas and $5 tubs of popcorn? Don't we answer to a higher authority about how we spend our money as opposed to obeying the profit-minded theatre's rules? I think this falls under being a good steward and thus makes my "sneaking" food in okay. What do you think?