"Whatever the social effects of talk radio or the partisan agendas of certain hosts, it is a fallacy that political talk radio is motivated by ideology. It is not. Political talk radio is a business, and it is motivated by revenue. The conservatism that dominates today's AM airwaves does so because it generates high Arbitron ratings, high ad rates, and maximum profits."
January 1, 1970
https://en.wikiquote.org/wiki/David_Foster_Wallace