My husband sells these ads. His company prints the bulletins at no cost to the parish, relying on the advertising revenue to cover the cost of printing. At the end of the year, if certain conditions are met, the parish may receive a portion of the ad revenue. He sells to businesses in the general area where the churches are, but not necessarily only to parishioners. A very large percentage of the businesses renew the ads year after year. Advertisers are happy with the ads because people keep the bulletins at home and because they are placed in people's hands week after week for a full year for consistent, repeated exposure. Many include a coupon so they can see exactly how many of the customers are coming from the bulletin ads. Apparently, it's enough.
Businesses represented in the ads include restaurants, hardware stores, contractors, pharmacies, doctors and counselors, veterinarians, real estate agents, spas and hairdressers, auto repair shops, funeral homes, florists, plumbers, nursing homes, supermarkets, health clubs, etc., etc., etc. Basically everyone in the neighborhood.