While consumers only see the great money-saving bargains — for instance, $40 worth of food at a local restaurant for $20 — merchants have to accept that running a Groupon-type deal is probably going to be a money-losing proposition in the short term. Since Groupon typically gives merchants 50 percent of its deal revenue, that means that Joe’s Restaurant is only receiving $10 for giving away $40 worth of food. Low-margin businesses like restaurants will often lose money on that — and the losses will add up, since Groupon can sell hundreds or even thousands of coupons at a time.

The silver lining for businesses that use Groupon — and the entire premise of ‘daily deals’ in general — is customer acquisition. The idea is that by getting a whole bunch of people to try your food (if you’re a restaurant) or services (if you’re, say, a yoga instructor) you can get a certain percentage of those deal purchasers to come back later and pay full price.