Italy’s restaurant trade was accused of ripping off tourists last week in a mass protest by catering workers on the streets of Naples. Delighted tourists in the Piazza Dante were handed free margheritas as members of the Neapolitan Pizza Chefs’ Association (APN) served up thousands of pizzas as a protest against the rising cost of Italy’s most famous export.

“Consumers beware,” warned the APN president, Sergio Miccu. “A margherita pizza shouldn’t cost more than £2.80,” adding that the average cost of producing the quintessential Neapolitan dish is just 96p.

“In some cities I’ve seen margherita pizzas being sold for £8,” said the regional agriculture chief Francesco Borelli. “Considering the low cost of the raw materials, that’s real financial speculation.”

Public dissent against overcharging is increasing across Italy. Two weeks ago, an English tourist called police to a bar in Tusa, in Sicily, after being charged £28.95 for three sandwiches; and a German couple who recklessly ordered a lobster lunch at an outdoor table in St Mark’s Square, Venice, paid the restaurant £400 for the experience.

The national consumer protection watchdog Codacons says it is receiving 20,000 complaints a year from ripped-off locals and visitors alike, and it’s not only restaurants who are guilty. The report cites a ring of 40 Roman taxi drivers caught charging tourists £104 for the journey from Fiumicino airport, a fare that is officially fixed at £32; Venetian ticket sellers caught charging tourists £58 for £45 vaporetti passes; and a plumber who charged a tourist £800 to unblock the sink at a rented villa.

Two-tier pricing is another rip-off, with forestieri - foreigners - frequently paying one rate and locals paying another. “In many cities there are two or more distinct price lists,” explained Marco Donzelli of Codacons. “Residents pay one price, which increases slightly for Italian tourists and is decidedly steep for foreigners.”

“They cannot tell us what to charge,” argued a Venetian pizzeria owner who asked not to be identified. “Most people who visit Venice think nothing of paying €10 for a pizza. It’s all part of the experience.”

Codacons warns that Italian laws requiring tariffs to be openly displayed are frequently ignored and advises visitors to check prices before starting journeys or ordering in bars and restaurants. “If they don’t offer you a menu, ask for one,” it says. “Otherwise you could find yourself paying £24 for a simple spaghetti carbonara.”

“Unfortunately, in Italy, as elsewhere in the world, there are dishonest and unscrupulous people who will take advantage of tourists,” said the Italian Tourist Board. “We do not try to hide their actions, but highlight them, so visitors are aware. If a tourist believes he has been ripped off, our advice is to get a receipt, or other evidence, and report it to the police.”

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