Travel ads and air travel ads are not the same thing. If you put up a billboard showing some cool/interesting place, people will be fractionally more inclined t

Travel ads and air travel ads are not the same thing. If you put up a billboard showing some cool/interesting place, people will be fractionally more inclined to go there - although as I said above, I think people mostly think of places they want to go and then use advertising to help choose who to give money to to achieve that end. Ads for airlines aren't encouraging people to fly so much as inviting them to choose one carrier over another. If you have X people going from Den Haag to Neu Amsterdam and there are multiple airlines serving that route, then airlines have to compete on price, comfort, customer service, etc. Nobody looks at an airline advert and then tries to think of a place to go in order to enjoy flying on a plane.