Neither recipient had anything to do with setting up those fundraisers.
That didn't stop the sites from raising tens of thousands of dollars, while campaigns on similar "crowdfunding" sites have raised millions combined for other victims.
That's on top of the nearly $28 million given to The One Fund, a more traditional relief fund established by top state officials.
Such giving is the reliable flipside to tragic events, with the Internet bringing heightened levels of immediacy, publicity and generosity. But charity watchdog groups warn not all giving opportunities are equal, with online drives more prone to confusion, scams or misuse of money.
An advantage to crowdfunding sites, which essentially provide a platform for individuals to set up their own fundraising efforts, is the speed at which they can start soliciting donations. For instance, the site GoFundMe had marathon victim relief campaigns going by 10 a.m. the day after the bombings. It now hosts more than 40 individual marathon-related campaigns that have raised $2.7 million.
But that ease of setting up a fund drive means less scrutiny of the fundraisers using the sites, which may be known only by a picture and a short testimonial.
"There may be little oversight going in, in terms of how the money is actually spent, and whether it's going to the appropriate parties," said Bennett Weiner, chief operating officer of the Better Business Bureau's Wise Giving Alliance.
Examples of fraud after tragedy are plentiful. After Hurricane Katrina the FBI found 4,000 bogus websites that stole donors' money and personal identification.
And it raises questions when the beneficiary of an online campaign doesn't even know about it.
Henneberry, of Watertown, said he had "nothing, nothing, nothing" to do with any drives to raise money for a new boat.
A spokesman for the Martin family said it has approved only The Richard Family Fund, which has its own site.
The lack of an initial connection with a fundraiser doesn't mean the money won't eventually get to the intended recipient. A spokesman for Crowdtilt, where a campaign And bombing victims say the sites offer a convenient way for people to directly give to their specific needs, and can be tremendously encouraging.
" My sisters and mother would read the comments (from donors) to me while I was in the hospital, and it really helped me in my recovery there," said Brittany Loring, the beneficiary of a campaign on the GiveForward site. Loring required three operations after her left leg was badly injured by shrapnel from the first blast.
Massachusetts Attorney General Martha Coakley's office is checking out fundraisers and has yet to find fraud, said spokesman Brad Puffer. But it's promoting vigilance.
"We simply encourage people to do their homework and give wisely," Puffer said,
Ken Berger of the watchdog group Charity Navigator prefers well-established charities or credibly backed efforts like The One Fund, founded by the governor of Massachusetts and mayor of Boston.
Such groups leave long paper trials and do robust vetting before they distribute money, he said. The tradeoff is the process takes weeks, which can be a lot less satisfying than an instant Internet donation, he said.
Berger added, "The faster you go, the greater the risk."
Dan Borochoff, of Charity Watch, said the same emotions that spur remarkable giving are used to take advantage of people. Ultimately, Borochoff said, people are free to throw their money away, but they shouldn't make it easy for the people trying to take it.
"Ignorant bliss is what they are going for," he said. "If you really care, you're going to be more responsible."
Brad Damphousse, chief of executive of GoFundMe, said his site takes significant steps to verify campaign organizers, including checking the linked Facebook account and affirming account payment information.
He added there's a natural social safeguard, since strangers usually won't donate to a site until they see dollars from an organizer's closest family and friends first.
"The earliest donors are essentially vouching for the authenticity of a given campaign," said Damphousse, whose company charges a fee of 5 percent of each donation.
Tom Teves, whose oldest son, Alex, was one of 12 killed during the 2012 movie theater shooting in Aurora, Colo., said raising money is an irrelevancy to someone in the midst of grief. But he and other family members of mass murder victims are pushing a National Compassion Fund, which he described as similar to The One Fund, to increase equity and transparency for victims.
Having a primary entity collecting and distributing money transparently can simplify things for people going through the unthinkable.
"You don't understand where you're at," Teves said. "You're just trying to literally figure out how you are going to stand up and keep breathing."
Erika and Leonardo Galvis, whose parents were badly injured in the marathon bombings, said they didn't think to set up a campaign on GiveForward until days after the bombings, and then only after their parents had been through surgeries that pointed to a long recovery with large and uncertain costs.
It's not easy to think in such practical terms amid the shock and disbelief over what happened, Erika said.
"It's very hard to focus on the fund," she said. "But we have to do it."
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