Many shoppers notice that supermarkets lack windows, making it easy to lose track of time as afternoon light turns to dusk outside. Rather than a psychological trick to keep customers spending, this design primarily serves practical needs like controlling heat, protecting sensitive food, and optimizing indoor temperatures. Windowless walls also provide maximum flexibility for arranging tall display shelves, avoiding glare on packaging, and managing complex refrigeration systems. While some modern grocery stores now incorporate skylights for natural light, overall layout choices remain driven by energy efficiency and practical store organization.