In 1970, less than 18 percent of U.S. households consisted of just one person—households with five or more people were more common, accounting for just over 20 percent of households (see Figure 2). Over the next three decades, the share of such large households shrank below 11 percent, while the share of one-person households expanded to nearly 26 percent of the total. - Population Reference Bureau

That's why. People living alone don't make meals as much as heat stuff or order in. The recipes in this forum are all written for one person, and most are very simple and quick. Some of them can be made in less time than it takes for a pizza to be delivered.