Why have movie ticket prices gone through the roof?

Average movie ticket prices have hit an all-time high of $8.61, a 28 percent jump from last summer, according to new data from the National Association of Theater Owners. (Of course, moviegoers in New York City and Los Angeles typically spend twice as much.)

With streaming services and other entertainment platforms making inroads on consumers' leisure time, it may seem like a strange time for the movie biz to make its product less accessible.

But there are some good explanations for why you're shelling out mega-bucks to see those diminutive "Minions":

Also Read: 5 Headaches That Wrack Movie Theaters Despite 2015's Box Office Boom

1. "You gotta see it in 3D!" … and pay an extra $3
One of summer's biggest stories has been the resurgence of 3D and the success of IMAX and Premium Large Format theaters. Three billion-dollar blockbusters — "Furious 7," "Avengers: Age of Ultron" and "Jurassic World" — were action epics ideal for mammoth screens and drew fans in record-breaking numbers. Last weekend, "Ant-Man" became the sixth No. 1 movie of the summer to have more than 40 percent of its grosses generated by 3D screens, a level of success and consistency not seen in years. Both formats bring surcharges of $3 or $4 per ticket.

"Basically, everyone has gotten smarter about 3D," ReadD President Anthony Marcoly told TheWrap. "The studios are better at picking which movies should be 3D, the theaters are doing a better job of finding the right number of screens for them and consumers are picking their 3D movies, so they go home happy and come back."

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3. Can we show you something in a 14-screen multiplex, Mr. Alibaba?
With deep-pocketed Chinese investors like Wanda Group buying theater chain AMC and Hollywood studios' movie slates looking strong, it's a great time to own a U.S. theater chain — or to sell one. As most potential sellers do, many of the larger chains are investing in expansions, refurbishments and equipment upgrades — and passing along the costs to ticket buyers.

4. That's not an usher, that's a concierge
With Netflix and others making serious inroads on moviegoing, particularly among young people, some indie chains like Alamo Drafthouse and Landmark Theaters are putting on the ritz to provide an experience superior to home viewing (or at least most of our homes). They offer patrons valet parking, reserved seating, lounges with luxury recliners, ultra-sound, fine dining and booze. It may pay off ultimately, but right now it doesn't come cheap, and the entry price goes uptown, too.

5. Plain old inflation