Some senior fundraisers are asking their colleagues to boycott donor advice website Intelligent Giving after it published a report criticising face-to-face fundraisers.
Dianne Flatt, director of fundraising at Epilepsy Action, has been using networking website Facebook to encourage her peers across the sector to snub the site after last week's report.
Flatt said the report was "idiotic" and that Adam Rothwell, director of Intelligent Giving, was working against charities at a crucial time.
"We need to be positive now, and this man is just bringing the whole thing into disrepute for no good reason," she said. "I am saying avoid the site - don't use it at all. It is not a good representation. It is all about personal prejudice."
Rothwell said: "We still stand by everything we have said about chuggers. It's a shame if people don't like it, but that's up to them."