Another pop-up, American Field, debuted in Boston the weekend before NorthernGRADE Chicago and featured 40 vendors, organizer Mark Bollman said.

"It's one thing to read about companies making things in the U.S. or to check a label, but I think it's a whole other thing to have a physical representation of like-minded companies in one place," said Bollman, founder of Boston-based outfitter Ball and Buck. "You can directly see and understand the growth of this movement and really understand the impact of a purchase, be it big or small."

The markets featured a combination of businesses that use American factories and workshops to produce their goods along with artisans and crafters who, by virtue of living in the United States, make their product here. Across all categories, the raw materials may or may not be domestically sourced depending on availability, with hardware such as zippers, snaps and woven fabric among the materials in shortest supply in the United States.

The growing hype has some worried that "made in America" is on the precipice of becoming a passing style trend before it actually has a chance to realize its oft-cited underlying goals.

"The initial made in the USA message was about bringing jobs back to the country to stimulate the economy, ending the dependency on other countries for goods and bringing back the education and know-how that comes along with the industry. All that's being diluted and boiled down into the message of buy made in the USA. The bottom has been taken out and become a selling point," said Chicago-based menswear blogger and digital strategist Brad Bennett, who helped coordinate NorthernGRADE.

It's unclear whether interest in American-made clothing correlates with an increase in industrial domestic manufacturing of clothing, which declined by 0.7% from September 2011 to September 2012, according to the Federal Reserve's numbers on industrial production. However, preliminary numbers for September showed a 1.6% increase over the previous month.

That's where the markets come into play, to create a movement by bringing together consumers, brands and retailers who are doing their part to raise the profile of American-made fashion.

"It's definitely a celebration of things made here but also a celebration of the people making it," said Bennett, whose blog, Well Spent, features "obtainable, honestly crafted goods" from the United States and abroad.

"It's a pretty cool thing to pick up a bag knowing it's going to last the rest of your life and then shake the hand of the person who made it," he said. "You're not just coming to NorthernGRADE to spend money, you meet people and it's sort of like, here's your community."

It's a doggedly enthusiastic community of people who are obsessed with craftsmanship and design. They're not only entrepreneurs but experts and storytellers who can spin a loooong yarn on the virtues of selvedge denim, waxed cotton and Chromexcel leather. Like Tony Patella, co-founder of Tellason jeans, who explained in an hourlong phone interview why the weave and dye of his denim makes it more expensive per yard compared to denim used for jeans in the mass market.

A big part of selling made in America is educating the consumer on what they get from their investment, said Lesli Larson, co-founder of Archival Clothing, whose best-selling roll top backpack goes for $220.

"You pay upfront, but you buy sparingly and wisely with the idea that you're going to use this piece for many seasons and eventually you get pennies per wear," she said.

Her business grew out of her blog, which documented "long-lost artifacts" from Montgomery Ward catalogs and Americana-inspired fashion being produced in Japan with old machines and equipment purchased from the United States.

"The shift of moving past a state of nostalgia to what can we do to make this a reality using available resources has been the challenge," said Larson, who has kept her job as an archivist at the University of Oregon-Eugene even as her business has grown.

Larson relishes the opportunity to share her knowledge, which she did with fans including Adachi, who spent more than three hours floating around the showroom before deciding to drop $300 on an Archival vest. His girlfriend's big-ticket purchase was a pair of Tellason jeans for $198. They were confident that the purchases were worth the money, not only for their quality but because of the stories behind them.

It reminded Adachi of a TED Talk by Simon Sinek who put forth the idea that people don't buy what you do, they buy why you do it.

"I'm the type of person who's more interested in why," Adachi said.

For others, though, the origin of the goods was not nearly as important as their quality.

"I came to the event for the uniqueness of the collections," said Jeff Medchill, a mortgage industry auditor who also picked up a pair of Tellason jeans. "American-made is not a strong point, I wouldn't go out of my way to avoid or buy American-made."

Collin Moody said he was drawn to the event because he supported Chicago-based retailers Haberdash and Penelope's, which were showing at the market. Normally, not everything they carry in their stores is domestically made, reflecting a commonly held position among consumers and stockists that buying made in America is secondary to sourcing high-quality products made responsibly regardless of their origin.

"We're interested in the ethics of the products. We try to be conscious of where they come from and who's making them," said Moody, 21, also a student. "It also helps us not be wasteful."

For retired carpenter Paul Hortenstine, the market was simply an opportunity "to find quality products made in the USA."

He and his wife made the trip from Shorewood, Illinois, after learning of the event on Twitter. He had his sights set on a Stormy Kromer trapper hat, but stopped on his way over to quiz George Vlagos, proprietor of Oak Street Boots, on the origin of material for his footwear (Horween Leather of Chicago).

"This guy from Oak Street Bootmakers, he's making quality product. I'm all for seeing people succeed making quality products in the U.S.," Hortenstine happily exclaimed as he walked away without purchasing a pair, which run from $200 to $500.

"The price is high but quality justifies it," he said. "Maybe you can buy it all or you can focus on one or two things."