Long ago, before the internet was invented, brands hoping to attract new customers cooked up the idea of handing out free samples. It remains a tried-and-true method for many brands today. Dunkin’ Donuts and Krispy Kreme hand out free donuts on National Donut Day, for example. In July, 7-Eleven celebrated its 90th birthday by giving out free Slurpees for a solid week. And the legendary free sample tables at Costco are said to draw fans who can assemble an entire meal from the giveaways.