A chorus of "Wow's" and "Thank you's" went up from the customers, followed by a round of applause.
Then came the outpouring of gratitude, and tears from angels, customers, and Kmart associates alike.
"It couldn't come at a better time. I just had a fire and lost everything," said teacher Stacey Heyward, wiping away tears from her eyes. She and Karchawer hugged. The layaway angels took care of the remaining $200 balance on her layaway plan, which included Play-Doh, dolls for her daughter, and tools for her son who had recently graduated from technical college.
"I feel like someone just gave me a million dollars," said Nancy Gomez, a Mary-Kay saleswoman. The day before she was making calls to try to borrow money to pay off the rest of her layaway plan. To save money this year, her family had agreed to only give the kids presents.
"I can't explain how I feel right now," said Matrice Everett, a homeless shelter worker who says she lives paycheck to paycheck and turned to layaway after her credit rating fell. "This is really Merry Christmas."
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Hearing stories like those, said Karchawer afterward, "that's the kind of thing that rips you up." Growing up middle-class in upstate New York as the son of two teachers he said he usually "got everything he wanted" for Hanukkah. So as an adult, he wanted to give back, but didn't know exactly how or where.
Then, after he won an online photo contest by drumming up votes on social media, he got the idea to channel that power to make "mitzvahs" happen. Pay Away The Layaway was born.
The first year they raised $2,000 from 75 people. This year, lifted by a mention in stories about Tebow's own layaway angel efforts and a successful campaign on crowdfunding site indiegogo, they're on track to raise over $10,000.
To make sure they're not just helping some guy get his big-screen TV, the group works with the store to identify and pay off plans that mainly have just toys.
Besides the Bronx, this year his group will hit up stores in the Bay Area, Chicago, Washington D.C., Seattle, Tennessee, and elsewhere.
"I wish we could do more," he said, his eyes growing red and wet under the store's fluorescent lights.