I have experienced this many times. It is a big frustration. You search for the best offer to travel on a romantic trip in Europe (let us say). After a lot of time you find the best and cheapest alternative, and you click back to that website. But suddenly, the ticket is a lot more expensive than it was.
The last time in happened to me was last week, when I was going to book our flights to our next trip. First I searched for one person, and the price was affortable. Then I searched again at the same search engine, but this time for two people, and the price per person had gone up. When I searched for the third time the price had gone even more up. And it was pretty annoying, I have to admit. But two days later the prices were down again, so I booked. I am not the only one that have experienced this, and feel that way when the prices of flight tickets goes up the more you search for it.
Others say, it did not happen to them when doing these two things. I have never tried to delete the cookies. But I have changed the computer, and have also experienced three different outcomes. The same price, cheaper price and more expensive price.
No one have still not managed to document that airlines actually take up the prices based on cookies, so this is still just speculations.
My parents were travelling with some friends last summer. My dad found a great offer, and sent it out to all the friends that was going to join the trip, for see if they found the fare of the flight ticket fine. As everyone clicked on the same trip for the same dates, the flight ticket suddenly got a lot more expensive from one day to another. Probably because the airline though the demand was so big, as many different people were searching on the same flight.
As no one doing research on this issue, actually could confirm or disconfirm that cookies are used to adjust the prices of flight tickets. Most people have experienced that it get much more expensive the more they search.
Though it is frustrating, I can understand if airlines do this. As in all other business sectors, the airlines will always try to get as well paid for their products as possible. And that the prices therefore are continuously adjusted according to what they expect to get out of the market, makes sence.
Have you experience that the price of a flight ticket goes up the more you search? If so, why do you think the prices goes up?