Movie theaters have had a rough 12 months. Due to pandemic prohibitions and the public's general hesitations about taking part in large indoor gatherings, multiplexes are no longer the entertainment hub they once were.

But as vaccination rates increase, so does optimism. Box office numbers are growing, and it may not be long before attendees are enjoying summer blockbusters with a lap full of food. Pricey movie theater concessions, after all, are responsible for roughly 40 percent of a cinema's profits. (Ticket prices are shared with film studios.) Whether you’re among those anxious to return to the theater or choose to opt out for a bit longer, take a look at some interesting facts behind the concession business.

1. The first movie theaters banned snacks.

As some of the earliest films began to unspool across screens in the 1920s, cinema houses had a widespread policy: No food was allowed. Movie theater managers saw their operation much like live theater, with a slightly reverential atmosphere. Smacking and slurping was considered distasteful. Worse, popcorn and other snacks would inevitably spill and ruin their ornate carpeted floors. But when silent films gave way to “talkies” and a steady sound could help muffle chewing, many theaters began to ease restrictions.

2. Movie theater snacks were originally peddled by vendors.

Movie theaters used to have vending machines for snacks.mj0007/iStock via Getty Images

While talkies may have relaxed attitudes about theater food, cinemas still weren’t equipped to dish out a variety of snacks. It was easier for owners to make arrangements with popcorn street vendors, who were typically lingering outside and handing off bags of fresh popcorn to incoming attendees. The theater took a daily fee, and popcorn vendors were free to sell to ticket holders as well as passersby. Theater owners also allowed candy vendors to install machines in their lobbies.

Eventually, managers got wiser and purchased popcorn machines of their own. Best of all, the popcorn’s delicious aroma permeated movie theater lobbies—making for the perfect sales tool.

3. Snacks may have saved movie theaters.

The Great Depression saw fewer and fewer people with disposable income for entertainment, and many theaters went under in the 1930s. But movie theaters that had started serving snacks seemed to persevere. At 10 cents a bag, popcorn was cheap enough for moviegoers and the profits from snacks helped keep owners afloat. (Milk Duds, another inexpensive treat introduced in 1926, were just 5 cents.) Soon, customers considered movies and snacking to be an agreeable combination. By 1945, 40 percent of all the popcorn consumed in the U.S. was consumed in theaters. With wartime sugar rations on, it became the de facto snack.

4. “Let’s All Go to the Lobby” has a murky past.

If you’ve been to the movies, you’ve probably seen the “Let’s All Go to the Lobby” animation, the peppy rallying cry to visit the concession stand as rendered by singing boxes of popcorn and candy and set to the tune of “For He’s a Jolly Good Fellow.” It’s an example of a snipe, or a short film played before movies that informs or cautions attendees about things like talking. Animator Dave Fleischer (Popeye) produced the short via Filmack, which released it in 1957, and it has since become a retro favorite. But because Filmack records were destroyed, there’s very little information about how and when it was produced.

5. Movie theater butter isn’t really butter.

Movie theater popcorn will always taste different than microwave popcorn, and it’s not just because it comes from a popper. Most movie theaters use coconut oil for popping, which infuses the treat with 90 percent saturated fat. One of the other major secret weapons is Flavacol, a powdered salt seasoning used by theaters to give popcorn a buttery yellow tint and a salty flavor. It’s not actually butter, though, and neither is the “butter” poured over the kernels. That’s usually a topping made with soybean oil, beta carotene, tertiary Butylhydroquinone for shelf stability, and polydimethylsiloxane to prevent foaming. This butter-like concoction helps prevent popcorn from getting soggy.

6. E.T. caused a movie theater snack frenzy.

E.T. changed the movie theater snack game. TriStar Media/Getty Images

While the simple act of walking into a movie theater can provoke an appetite for snacks, some movies can prompt a race to the concession stand. In 1982, director Steven Spielberg’s E.T. the Extra-Terrestrial was released and caused a veritable stampede to the counter after the alien was seen munching on Reese’s Pieces. (Hershey agreed to have the candy featured in the film after Mars, which made M&Ms, declined; Jack Dowd, Hershey's vice president of new business development at the time, signed off after making sure E.T. wouldn't be “an X-rated space creature.”) Hershey set up theater displays in 800 locations and offered free stickers and T-shirts to patrons buying the bite-sized treat. Overall sales shot up 70 percent one month after the film’s June release. Not bad for a candy that wasn’t even mentioned by name in the movie.

7. Moviegoers can smuggle in some very weird snacks.

Since the introduction of the cinema itself, patrons have tried to carry in outside snacks. When theaters had no food to offer, it was understandable. But theaters generally frown on spectators who come with their own food, as it severely cuts into their profits.

There’s another reason for the "no outside food" rule however, and it's simple: Some food can be stinky. In 1992, Tom Kiefaber, the then-owner of Baltimore's renowned Senator Theatre, told the Baltimore Sun that past customers had brought in smelly fish sandwiches, an entire pizza, and 12 steamed crabs, the shells of which they had left in the theater.

8. The mark-up on snacks is enormous.

Popcorn has a very high mark-up.YvanDube/iStock via Getty Images

With snacks being key to a movie theater’s profits, it’s no wonder the mark-up can produce some sticker shock. An $8 popcorn might cost just 90 cents in materials, giving the snack an impressive 800 percent return on investment (ROI); a $6 soda could be less than $1 worth of syrup, water, and cups for a 600 percent return. No wonder they can afford to offer free refills.