Quote from : Rethinking Worldview: Learning to Think, Live, and Speak in This World Book

... we met with more closed doors than open ones -- and the people who answered our knocks were invariably older. Young people didn't aswner the door to strangers, who would undoubtedly be trying to sell something, any more than they would answer the telephone to telemarketers once Caller ID came along. The only people we encountered going door-to-door were the ones old enough to remember when that's the way the world worked.