The annual event known as Free Comic Book Day is held the first Saturday in May every year—May 5 in 2012. It’s a day when comic book shops all over North America give away free comics to each and every customer. It’s also a huge day for selling comic books.
The list of freebie comics being given away changes from year to year, and the 2012 lineup includes titles featuring the Transformers, Buffy the Vampire Slayer, the Smurfs, Spider-Man, Donald Duck, and the Avengers (fitting considering the “The Avengers” movie opens this weekend), as well as many lesser-known characters. Which shop you visit—and how many people get there before you—will determine which free comics are available. Every customer is guaranteed to get at least one, and perhaps a few books, though.
Hundreds of stores are hosting book signings by writers and artists on the big day as well. One shop in Chicago, for instance, is welcoming Jeffrey Brown, creator of “Darth Vader and Son,” a funny look at what would have happened had Vader been an involved father rather than an evil Sith Lord helping to rule the galaxies with an iron fist. Tom Batiuk, of the “Funky Winkerbean” comic strip fame, is appearing at a comic shop in Cleveland.
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Why the big day of giveaways, which some might assume would be a money loser? Naturally, the long-term hope of Free Comic Book Day is that putting comics into the hands of young (or old) readers will turn them into lifelong devotees of the original American art form. (Come to think of it, isn’t this similar to a classic tactic practiced by drug dealers?)
Free Comic Book Day also seems to be good for business in a more immediate sense. Freebies have an odd effect on consumers: Often, they make people spend. One of the biggest sales days for Slurpees at 7-Eleven occurs on (you guessed it) Free Slurpee Day. Likewise, stores have discovered that giving away free samples to customers increases the chances they’ll buy something, likely due to a feeling of obligation, thankfulness, or guilt after being handed a food or product free of charge.
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The same effect takes place at comic book shops. A blogger at Forbes quotes Joe Field, who owns a comic shop in California and came up with the original idea for Free Comic Book Day:
“I’m told by a lot of retailers, and I’ll bear that out in my own store, that Free Comic Book Day is one of the best days of the year in terms of business. We use Free Comic Book Day as a way to just get people ignited about comics … and to come back to the store week after week. It turns out, with the number of people who show up, it’s no secret that it’s become one of the best business days of the year.”
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In other words, while you’ll get something—or perhaps a few things—for free on Free Comic Book Day, you’ll still probably want to show up with some cash.
Brad Tuttle is a reporter at TIME. Find him on Twitter at @bradrtuttle. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.