Restaurants on The Pearl-Qatar have lost more than half their turnover since a ban on alcohol was introduced on the vast man-made island.
Restaurants on The Pearl said they received notices from its developer, United Development Company (UDC), on various dates in the second week of December that they had to stop selling alcohol. UDC declined to comment.
"The first day it was suspended almost 100 people [either cancelled bookings or] walked out when they found out there was no alcohol," said Rey Tumulak, the head waiter at the Bice Ristorante on The Pearl-Qatar.
He said revenue at the Italian restaurant was down by more than 50 per cent because of the alcohol ban.
Restaurants on the huge development covering some 4 million square metres off the coast of Qatar were told about a month ago that the sale of alcohol was to be suspended "until further notice", Mr Tumulak said.
The Pearl-Qatar was designed as a dining, marina and residential destination, described by its developer as the "Riviera Arabia".
Amily Chompoo, a supervisor at the Mango Tree restaurant on The Pearl, said there had been a decline in revenue and a definite shift in the demographic of its customers since the restaurant had stopped selling alcohol.
"Most of the guests now are local Qataris," she said.
Mr Tumulak said alcohol was a vital part of Bice's profitability.
"Let's say for two people, the maximum for food they consume is 400 to 500 [Qatari] rials.
Most of the people will have alcohol for almost 1,000 rials [Dh1,008].
So you can imagine, in a group, they consume 2,000 for food, but they consume 3,000 to 4,000 for alcohol."
"Alcohol is obviously a sensitive issue in many Muslim countries," said Chiheb Ben Mahmoud, the head of hotel advisory at Jones Lang LaSalle Hotels, Middle East and Africa.
"Therefore, managing the open sale of alcohol is always a delicate balance.".
He added that tourism in Qatar was unlikely to be affected by the ban.
"Qatar, as an international and regional tourism destination, is more associated with sports, culture and high-level public meetings and conferences," Mr Ben Mahmoud said.
"Alcohol in such context is not as central as it would be in Ibiza, say."