Halloween in the U.S. has grown into a nearly $7 billion mass-market juggernaut that's second only to Christmas. This year, Americans are expected to spend $2.5 billion on Halloween costumes, and the average person will shell out more than $72 on Halloween candy, costumes and décor. That's the most Americans have spent on the holiday during the National Retail Federation's nine-year history of tracking the category.

So how did Halloween get supersized? To find out, we asked Marc Beige for some insight. Having served as the president and CEO of Rubie's Costume Co., in Queens, N.Y., for nearly 40 years, he knows a thing or two about the history of Halloween.

After the "Candy Scares" of the 70s, Halloween parties quickly arose, as did full-length, wearable costumes for children and adults. Although today most of Rubie's more than $100 million in revenues stem from children's costumes, outfitting adults accounts for 40 percent to 50 percent of the business. And business is good.