BENGALURU, March 26 -- On a recent weekend, a quick commerce firm set up a sampling stall inside a 130-apartment Bengaluru housing society, offering freebies, app discounts and instant deliveries to residents. Within hours, orders from that cluster spiked.

That playbook is moving from experiment to strategy. Brands are increasingly targeting gated communities as high-value consumer clusters, drawn by stronger word-of-mouth, higher repeat purchases and more predictable demand as digital advertising gets crowded and less efficient.

Nearly 32 million households live in such clusters across India's top cities, according to Redseer, which estimates they could drive close to $900 billion in consumption by FY31. What was once another urban seg...