"On behalf of Tim Hortons we sincerely apologize," said Michelle Robichaud, manager of public relations and social media, in a statement on Sunday.
"The regretful actions in a moment of frustration at one of our Vancouver locations (are) not at all reflective of our brand and restaurant owner values."
Robichaud said the owner is committed to personally apologizing and making amends with the individual, and will be making a "meaningful" donation to the Belkin House, a local shelter.
The incident at the Tim Hortons was first reported on Friday by witnesses on social media. Arianne Summach heard about what happened from a friend who works across the street, and took to Facebook to express her outrage.
She wrote that the owner dumped a large bucket of water on the man, his dog and all of his belongings including his cardboard bed, while he was sleeping outside.
Summach's post — which urged a boycott of the Tim Hortons on Robson Street at Richards Street — was shared more than 4,000 times.
"I hate bullies, and it's never OK at any age for any person to kick a person when they're down," she said when reached by phone on Sunday. "I just wanted to do something about it just to make sure that the person who did it knew it wasn't OK and it wouldn't be tolerated."
The 24-year-old freelance marketer said she never expected the post to be shared so many times, and has been overwhelmed by supportive messages.
Summach said she was happy with the coffee chain's apology, but it doesn't go far enough.
"A donation will never make public humiliation OK. It shouldn't have happened in the first place. I think the person responsible should go above and beyond what Tim Hortons expects from him, and just apologize in a very big way if he ever sees this person again," she said.
Robichaud did not respond to emailed questions about whether the owner faces disciplinary action, and the Tim Hortons location could not immediately be reached for comment.
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