They declined to comment, but passed out literature saying they did not buy from puppy mills.
Six police officers monitored the scene, keeping a path on the sidewalk clear. There were no arrests or incidents, they said.
A few Corona del Mar residents watched the protest while they sipped drinks from neighboring Starbucks and Nékter Juice Bar.
Workers from Nékter complained to police that the protestors were hurting their business, and one worker yelled "Whore!" at a protestor giving a speech.
Camille Cegeilski, 13, of Corona del Mar, was on hand to support I Heart Puppies.
"We don't think it's right," she said. "They don't come from puppy mills. They could go be more productive with their time to go to the puppy mills."
Organizers said a
bout half of their group was from Orange County and Newport Beach.
Others traveled from Los Angeles and other Southern California cities. They wore T-shirts and carried signs with messages like, "Good dogs die when you breed or buy" and "Pet stores lie to your face."
Protester Amy Disston, of Wildomar, spent time talking to Starbucks patrons about puppy mills.
"It's just educating people. That's the big thing," she said. "They really don't know."
Some passersby, however, remained skeptical.
"I came here to do Starbucks," said Erle Halliburten. "We've always had something of a quiet, laid-back community. You hate to become the focus of a group to come protest like this today. And from what I've seen, none of the dogs (in the shop) look unloved. But I feel strongly to the right of free speech, if it's done properly."
Davis said that Sunday's protest was the "official launch of a sustained campaign" against the store. She declined to say when, or how often, protests would take place. One shop converted to a humane business model after three weeks, she said, but another took more than five months.
Protestor Elizabeth Johansen of Los Angeles said the shop was an embarrassment to the village.
"I think it downgrades the community," she said. "It makes them look trashy. They have a chance every minute to go humane. There's no excuse. We will fight it to the bitter end."