The Atlantic: How Restaurants Got So Loud - Fashionable minimalism replaced plush opulence. That’s a recipe for commotion

excerpt from about the middle of article:

According to Pearlman, the haute-casual dining trend also helps restaurateurs run bigger and more successful businesses. Constructing interiors out of hard surfaces makes them easier (and thus cheaper) to clean. Eschewing ornate decor, linens, table settings, and dishware makes for fewer items to wash or replace. Reducing table service means fewer employees and thus lower overhead. And as manywriters have noted, loud restaurants also encourage profitable dining behavior. Noise encourages increased alcohol consumption and produces faster diner turnover. More people drinking more booze produces more revenue. Knowing this, some restaurateurs even make their establishments louder than necessary in an attempt to maximize profits.