At Athens International airport the queues at ticket desks have grown prompted by action from some of the major airlines.
Several have stopped sales via travel agents and tour operators over payment concerns.
Turkish Airlines, Emirates and Qatar Airways are among the major carriers to have taken the action.
The travel agents association claim ticket sales worth about 100 million euros a month have been affected.
“These people (the travel agents) will be suffering. These people are losing business already to the recession and now they are losing business at the direct competition against the airlines,” explained George Paliaouras Hellenic Association of Travel and Tourist Agencies
Turkish Airlines, which has been flying to Greece for 68 years said the decision was “due to the unpredictability of the economic situation.”
Many passengers were losing patience having to queue to buy tickets.
“I think it’s a bad decision. They should be going on like normal as long as possible. It is not possible anymore for other people, like people with restaurants and who have to pay their suppliers, people who have gas stations who have to pay their suppliers. It will be the same for everybody and I think people should act as normal as possible,” said one passenger.
The International Air Transport Association (IATA) said it was up to individual airlines to decide which agents had ticketing authority.
Ryanair are allowing passengers to pay with cash after capital controls caused problems with credit card payments.