Products and services. New and old firms. Some had been included in past postcard deck mailings. Others were newcomers. As you can tell, word is spreading.
Most decks contain actual postcards, which recipients return to request the free enticement.
These are usually not postage-paid. Other decks contain only coupons, not postcards. Their offers are similar to those made on postcards, but people have to present them in person in order to get the special deal. This kind of group marketing has been going on since the 1970s, so even though you may not yet have experimented with it, you most likely have received a few postcard decks. Because 89 percent of companies who try them continue to market with postcards in decks, you've got to assume they work.