The difference seems to be that the news organizations that published the recent pieces — Gawker, BuzzFeed, The Huffington Post and Mashable among them — do not see invented viral tales as being completely at odds with the serious new content they publish alongside them. The Huffington Post won a Pulitzer Prize in 2012, Gawker was among the first to report the cocaine use by Toronto’s mayor, Rob Ford, and BuzzFeed is building teams of investigative and foreign correspondents. Of course, websites like these are not the only news organizations to be seduced by stories that are too good to be true. In just the last month, CBS’s venerable “60 Minutes” had to apologize for taking too credulously the claims of a security agent about the 2012 attack on the American diplomatic mission in Benghazi, Libya.

Instead, editors at these sites acknowledge frankly that there are trade-offs in balancing authenticity with the need to act quickly in a hyperconnected age. “We are dealing with a volume of information that it is impossible to have the strict standards of accuracy that other institutions have,” said John Cook, editor in chief of Gawker, which highlighted the essay on poverty, by a woman named Linda Tirado.

“The faster metabolism puts people who fact-check at a disadvantage,” said Ryan Grim, the Washington bureau chief for The Huffington Post, which reposted the fictional airplane tweets, the letter to Santa and the poverty essay. “If you throw something up without fact-checking it, and you’re the first one to put it up, and you get millions and millions of views, and later it’s proved false, you still got those views. That’s a problem. The incentives are all wrong.”

But Mr. Cook says he thinks that readers can tell which content is serious and which is taken from the web without vetting. “We assume a certain level of sophistication and skepticism of our readers,” he said.