Just hearing that someone else had made a similar donation at the Edmonton hospital where her elderly father was a patient was enough to encourage her to put her own money down and "give back" to the staff and others at the institution.
In doing so, Kavanaugh joined a trend that has spread from Yellowknife to St. John's and seen more than 10,000 cups of coffee shared through 30 such random acts of kindness at Tim Hortons outlets across the country.
Impromptu acts of altruism are nothing new, but this recent flurry of cross-country generosity centred on a simple cup of coffee could be a high-profile manifestation of something researchers who delve into this kind of thing say is an intrinsic part of the human psyche.
"People actually get more happiness from spending money on others than spending money on themselves," says Elizabeth Dunn, an associate professor of psychology at the University of British Columbia.
Giving to one another, she says, is a "fundamental precursor that we need in order to achieve the monumental feats of co-operation that have made our species so successful."
All of this, of course, may sound a little counterintuitive in today's me-first world where self-interest can be a pretty powerful motivator. But Dunn and fellow researchers in the U.S. and Africa have discovered people can reap a stronger feeling of happiness when they share their money with others.
Pass it on
"We asked people to predict what would make them happier, spending a particular amount of money on themselves or on somebody else, and they think it would make them happier to spend this money on themselves," she says.
"Then when we actually do the experiment and look at what makes them happier, in fact even with small amounts of money, as little as $5, they're significantly happier by the end of the day when they've spent the money on somebody else rather than on themselves."
None of this, Dunn suggests, is to say self-interest isn't important.
"People are buying way more coffees for themselves than anybody else," she notes.
"But you know there is this important silver lining in the cloud of self-interest, which is that people genuinely care about others and seem to be built in such a way as to derive this happiness boost from helping other people."
While that "happiness boost" has resulted in a lot of free coffee across Canada lately, researchers suggest there is a more significant and potentially lasting impact from the random acts of caffeine-fuelled generosity.
"The human connection probably is and should be the important element," John Helliwell, the program director for the Canadian Institute for Advanced Research based in the Vancouver School of Economics at UBC, said in an email.
"The critical element here is the 'Pass it on' feature, with my good turn to you hoped to lead you to do good turns for others."
If the recent Tim Hortons numbers are anything to go by, there appears to have been an unusual "Pass it on" feature at play in recent days.
The iconic coffee-and-doughnut retailer has rebuffed any suggestions, cynical and otherwise, that these bursts of generosity are part of a covert marketing plan.
Instead, Michelle Robichaud, the company's manager of public relations and social media, said in an email that the company is "simply amazed at this uniquely Canadian phenomenon that is sweeping the country."
While it's not uncommon for Tim Hortons customers to pay it forward, and offer up money for someone else's coffee, "what has been happening across the country this past week and a half certainly doesn't happen every day," Robichaud said.
For those who do look into these kinds of things, however, there is little specific significance in the fact that the particular focus in this spontaneous generosity is a cup of coffee — Tim Hortons or otherwise.
"We tend to see this warm glow of giving beyond coffee," says Lara Aknin, an assistant professor of psychology at B.C.'s Simon Fraser University.
"Any time you're generally spending your money on other people, you get this warm glow. It doesn't need to be a warm-temperature caffeinated beverage. It could be a diet Coke and it might do the same thing. It could be a roll of sushi or it could be tickets to a baseball game."
'Emotional bang for your buck'
Whatever the commodity, however, that warm glow will probably be stronger if the person footing the bill observes the effect of their actions.
"You get more emotional bang for your buck … when you get to see the impact of your gift," says Aknin.
"In that vein, it's kind of wise to loiter and see the impact your coffee may have made on someone else. You'll probably get even more of this warm glow of giving if you stick around and see that."
For people who devote their careers to philanthropy in Canada, observing the current jolt in java-sharing is encouraging.
"As someone who works in the non-profit sector, it does my heart good to see that people are doing this," says Nicole Nakoneshny, a vice-president at consulting firm KCI and editor of Philanthropic Trends Quarterly in Toronto.
"It really does show that while it's not necessarily everyone feeling this way, there certainly is a sense within society … a genuine desire at different points in our lives, to support others and to share what we have."
Canadians are, Nakoneshny suggests, changing how they define philanthropy. No longer is it always seen as writing a cheque and receiving a tax receipt.
"An act of charity is exactly what these folks are doing — giving coffee to people through a Tim Hortons."
Other examples include crowdfunding, where groups of people come together with small amounts of money to support a particular cause.
Best use of $800?
No matter the definition of philanthropy, however, there could still be those who question the wisdom of a single individual investing several hundred dollars in double-doubles for folks they will never know.
“Many people may look at this and it does seem to me a little nutty to go in and buy $800 worth of free coffees," says Dunn, who co-authored a book entitled Happy Money, the Science of Smarter Spending.
"I don't know if it's the absolute optimal use of $800."
But Dunn says the research she's been involved with has found that even changing the way you spend $5 on any given day and redirecting it to do something nice for somebody else makes you happier.
"For people that find this intriguing, just try it," Dunn suggests. "It's definitely a cool phenomenon."
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