Many people attend Frontier Days just so they can refill their empty bottles of Little Johns Sarsaparilla Root Beer.
This happens at every festival Patty Mertz, owner of Little Johns, attends, she said.
Mertz, and Mel Theisen, both from near Kansas City, Mo., travel the country selling their homemade root beer and usually hear the same thing: their root beer is amazing.
Patty Mertz, owner of Little Johns Sarsaparilla Root Beer, fills bottles with root beer during the final day of Frontier Days 2014 Sunday.
"Since I hear it so often, I don't think I'm making it up," Mertz, who has owned the business for 25 years, said.
One of Mertz's favorite memories was when a little boy who was dressed as a Civil War soldier peeked over her counter and said, "In all my many years, this is the best root beer I ever drank."
In order to sell the root beer at events like Frontier Days and Civil War reenactments, Mertz had to research the history of root beer.
"You have to show that what you're providing was from that time," Mertz said.
She found a recipe from 1851 called Doctor Chase, an elixir which was sold as a blood purifier.
The drink had 2 ounces of sassafras, sarsaparilla, burdock, dandelion, spikenard and hops.
"He made it with hops," Mertz said. "I'm sure that's why he called it beer."
At the time, soft drinks were sold as elixirs that could cure just about anything.
"Coke could fix anything," Mel Theisen said jokingly.
Another requirement was that she couldn't sell root beer in paper cups. Mertz imports her bottles from all over the world, including Spain, Italy and Mexico.
She doesn't claim her root beer has any medicinal value, but the customers keep coming back.
Dan Kramer has been buying the root beer for "a long time," he said.
At home, he has more than a dozen bottles and brings them back every year for refills.
Kramer said the root beer he bought from a store a few days ago didn't compare to Little Johns'.
"I couldn't wait for the good stuff," he said.
Kramer's bottles were so old some parts broke off, but Little Johns replaced them when he returned for refills.
"We take care of our customers," Theisen, who has worked at Little Johns for 15 years, said.
At larger festivals, Little Johns has around 25 people working, including Mertz's children and grandchildren.
"I've put my grandkids and my own kids through it," she said.
Many people have copied Mertz's root beer, even former employees, she said.
"I guess being copied is a compliment," she said.
The root beer business has grown a lot over the last 25 years.
Mertz started by making root beer with a Boy Scout troop as a fundraiser, but then decided to turn it into a business.
"It's been a growing process," Mertz said. "It didn't happen overnight, that's for sure."
As she travels the country selling root beer, Mertz enjoys meeting the town people and vendors, she said.
"I like the camaraderie and the reaction between vendors and town people," Mertz said. "I get wonderful stories from the town people."
She heard of a couple that had root beer in a wooden keg. They put the keg in their living room and used it as a table and sometimes a seat.
"It blew up one day," Mertz said. "It's lucky no one was sitting on it."
Little Johns root beer returns to Frontier Days every year, so there's still a chance to get some root beer next year.
"It's an attraction," Kramer said. "If they weren't here, a lot of people would be disappointed."