Different prices are commonly charged to different groups of consumers for tickets at movie theaters, whereas the groups are charged the same prices for food and candy at the concession stands. The economic explanation for pricing tickets and concession items in this manner is that:

I think the explanation of this manner is that the concession items have a high-profit margin. It has more sales than the theater tickets. So to avoid the possible losses of income, the theater decides to make the prices of each item of concession stand must be the same to a different group of people.