For America’s graying cohort, often sectioned off by age at places like senior centers, the dining room of a fast-food restaurant is a godsend. It’s a readymade community center for intergenerational mingling. The cost of admission is low—the prices beckon those on fixed incomes—and crucially, the distance from home is often short. And that’s just one demographic.

In spite of the plastic seats, the harsh lighting, and, in many cities, the semi-enforced time limits for diners, people of all sorts can sit and stay and stay and stay—at birthday parties, first dates, father-daughter breakfasts, bible study groups, teen hangs, and Shabbat dinners. Or at supervised visitations and meet-ups for recovering addicts. For those who crave the solace of a place to call home that is not home, a fast-food dining room offers it, with a side of fries.

On a moment’s notice, a restaurant can also become a low-stakes venue for high-stakes assembly. The McDonald’s on West Florissant in Ferguson, Missouri, is typical-looking store. On a Sunday afternoon in the summer of 2015, it was offering respite from 97-degree Missouri heat and what must have been at least 95 percent Missouri humidity. About 30 people were inside, a mix of ages, mostly black, but also white, people in Cardinals hats, people talking on phones, people playing Vince Staples and Kendrick Lamar from small speakers at tables. If the crowd was bigger than normal for the time of day, it was because that Sunday was the one-year anniversary of the shooting death of Michael Brown a few blocks away; memorials and protests were taking place just outside, on the street.