GEORGE BERNARD SHAW once wrote: “There is no love sincerer than the love of food.” That love has limits, however. In thin years, diners value their wallets over their palates. Visits to posh restaurants in America declined by 15% between May 2008 and May this year, according to the NPD Group, a research firm. Fast-food restaurants, on the other hand, saw traffic decline only 2%.

To lure eaters back, many fine restaurants have done what luxury brands hate to do: have a cut-price sale. Some offer discounts to those who dine at unpopular times, such as early in the evening or on Sunday. Restaurant Week, a twice-yearly tradition in New York City where restaurants offer discounted prix-fixe menus at lunch and dinner, was extended by six weeks this summer. This may help. The 21 Club, a fancy joint in Manhattan, usually sees its business increase by around 25-40% during Restaurant Week, says Bryan McGuire, its general manager.

Many restaurants have also turned to the internet. Gilt and Rue La La, two popular online shopping sites that offer heavy discounts on designer clothing, have started to peddle meals at fancy restaurants too. Gilt, for example, recently sold a four-course meal at the Tribeca Grill, a restaurant owned by Robert De Niro, an actor, for $160 (36% off). Shopping sites like these attract image-conscious restaurants, because only the site's members can see that the restaurant has started to offer leaner prices.

Another website, Groupon, has gained popularity among restaurants as a way to bring in new customers. The company offers a daily discount in each of the 140 American and European cities where it operates. Some 40% of its promotions are for restaurants. The deals can be generous: some offer $50-worth of food and wine for $25. The deal only goes into effect, however, if enough people buy it. So people prod their Facebook friends to join the feeding frenzy. This type of “collective buying” has caught on. Since the firm started in 2008, it has brokered the sale of more than 8.8m “groupons” and saved customers around $375m. La Condesa, a restaurant in Austin, has sold 3,000 groupons. “It brings a lot of people into the restaurant who would never have come in,” says Jesse Herman, an executive.

Tasty offerings abound online. OpenTable, a website, allows people to book a table without having to plead with a snooty hostess. It also makes it easier for restaurants to track customers. SeamlessWeb allows people in America and Britain to search online for nearby eateries and order their food delivered. Even swanky restaurants have started to take part, betting that some people might want to eat haute cuisine without dressing for the occasion. But SeamlessWeb takes a cut of restaurants' sales for bringing them business, so restaurants have to decide whether it's better to stay hungry for customers or share part of their meal with someone else.