According to a Yahoo! Mail global survey of about 37,000 Internet users in 11 countries, 20 percent of U.S. residents admit buying products from spam purveyors. About 78 percent said they delete spam.
In Japan, by contrast, people deluged with junk e-mail are more active. Almost half of e-mail users said they send spammers angry replies to express their displeasure.
And, in a nod to how ubiquitous and popular e-mail has become, people around the world agreed that a loss of their e-mail would be more devastating for them than doing without radio or television.
Earlier this month, the Bush administration decided against creating a national do-not-spam registry to discourage unwanted e-mails, saying using current technology to do so might even generate more unsolicited sales pitches across the Internet.
The Federal Trade Commission said it feared that unscrupulous senders of unwanted e-mails would mine such a registry of e-mail addresses to look for new victims.
In May, an FTC rule went into effect requiring that unsolicited commercial e-mail that contains sexually oriented material include the words "SEXUALLY EXPLICIT" in the subject line.
The rule also bars graphic images from appearing in the opening body of the message. Instead, the recipient must take some action in order to see the objectionable material, either by scrolling down in the e-mail or by clicking on a provided link.
Yahoo! Mail is the Web-based e-mail service offered by Sunnyvale, Calif.-based Yahoo! Inc.