Man, 81, Becomes a Beloved 'Grandpa' to Staff at His Local Dunkin' After Tipping $280

Matt Cobo Gilbert "Gil" Walker

An 81-year-old man has become the most beloved customer at a Northern California Dunkin' after he left an envelope with nearly $300 to show his appreciation for the staff — and has since started a kindness war with the owner and employees.

When the coronavirus pandemic began in March, Gilbert "Gil" Walker tells PEOPLE that he could no longer meet his friends in-person at Peet's Coffee, where he had been a regular customer for years.

"Once this thing hit, we couldn't stay inside anymore so I started looking for places I could just drive-by and not get out of my truck," says Walker, a retired high school business teacher and athletics coach.

After going to a few places in Concord, California — his home of 57 years — Walker decided to try the new Dunkin' in his city and was immediately impressed by their "warm" staff after just a few visits.

"It had a different feel about it," he recalls. "The [employees] were so wonderful and so nice and friendly... When I retired in 2000, the only thing I missed was the kids and when I saw these employees, it reminded me of the kids I had in school."

Matt Cobo Gilbert "Gil" Walker and his wife Virginia "Ginny"

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While speaking to owner Matt Cobo one day, Walker learned that 14 people were employed at the Dunkin' and though Cobo had no plans to lay off anyone, he was forced to cut his employees' hours.

It was then that Walker came up with the idea to give Cobo an envelope filled with 14 $20 bills — a total of $280 — for each employee to show his appreciation. He did just that on his next visit in mid-March.

"I decided to do what I could to help out a little bit," Walker explains. "Life has been good to my wife [Virginia] and I, here in Concord... We're retired teachers, we're not rich, but we have enough to share with what we have."

"Every day, I'm greeted with warmness and love and affection, and it's just amazing," adds Walker. "I saw a way to give back a little and I couldn't think of a nicer group of kids than what I was experiencing at Dunkin', and I think Matt has a lot to do with that."

Following the kind gesture, Cobo says he and his staff couldn't believe it.

"It took my breath away," he recalls. "We didn't know how to respond. This was new to all of us."

Matt Cobo Matt Cobo (center) with some of his Dunkin' staff

In the time since that day, Walker has created a special bond with the Dunkin' staff, who affectionately call him "Grandpa."

Each morning, Cobo says they all look forward to his daily visits and providing him his usual order — an iced coffee with a maple bar for Walker, and an iced chai tea latte with less ice, almond milk, one less scoop of powder and cinnamon sugar for his wife (which has become known internally as "The Ginny") — free of charge.

"We love seeing him," Cobo explains. "So many of us are running on emotional empty right now, especially in the restaurant industry, so to have someone who's 81-years-old pull up to the drive-thru and get everyone excited like little kids, he's that emotional filler up."

Because they refuse to let him pay, Cobo says it has become "an incredible game of wits" between his staff and Walker.

No matter how many times Walker tries to pay, the employees and owner refuse, jokingly making excuses that the cash register is broken or the car ahead of him paid.

Cobo has even gone so far as to put up a sign that jokingly states, "Anyone who lets 'Grandpa' pay is terminated immediately."

Matt Cobo Matt Cobo's sign hanging inside Dunkin'

"What's so incredible for me is how the relationship with Grandpa continues to surprise me to this day," says Cobo. "It's like this story that doesn’t have an ending, it just keeps getting better and more interesting."

"The warmth of that place is incredible," adds Walker, who has resorted to jokingly threatening to hold up the drive-thru line so the employees will accept his tips. "Every time, I roll up to the service window, there are four or five kids hanging out saying 'It's Grandpa!' It's a great greeting."

More recently, the Dunkin' staff came together to throw Walker and his wife a 62nd anniversary party, as well as an 81st birthday party for Walker in the parking lot.

Matt Cobo Gilbert "Gil" Walker and his wife Virginia "Ginny"

The team also have plans to go over to Walker's home once the pandemic is over so they can have a barbecue and a backyard golf tournament, according to Cobo.

"This guy has given us so much," he adds. "He's just an amazing guy. He's funny, he's caring... He thinks he's getting more out of it, but really we get more out of it."

Notes Walker: "When it comes to the reciprocity and generosity, they're ahead of me and I'll never catch up... I've been through a lot of drive-thrus before, but I've never seen anything like this."

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As their "relationship keeps growing," Cobo says the interactions with Walker have taught him and his staff valuable lessons about kindness and hope.

"Everyone right now is holding onto hope for a better tomorrow, and what he does for us is he gives us that hope," Cobo says. "He lets us feel comfortable and confident in knowing that there is an end to this, and when it's over, kindness will continue."

"Things are gonna get better and they're gonna get better because Grandpa said so, and that's what we need right now," he adds. "Grandpa saying, 'This sucks but things will get better and I believe in you and I appreciate you.' How do you beat that?"

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