Groupon deals are usually 50 percent off, so that means merchants get paid just a quarter the face value of the coupon. (If you buy a $100 Groupon for $200 worth of spa treatments or food and wine at a restaurant, the merchant gets just $50). So why would merchants use Groupon if they're likely giving away their products and services at a loss? Simple: customer acquisition. The Groupon model benefits merchants in three key ways: 1)When you get someone inside the door, they're likely to spend more than the Groupon value. 2)People bring their friends. And 3) first time customers are likely to become repeat customers.