Bait advertising
Making an invitation to purchase products at a specified price without disclosing the existence of any reasonable grounds the trader may have for believing that he or she will not be able to offer for supply or to procure another trader to supply, those products or equivalent products at that price for a period that is, and in quantities that are, reasonable having regard to the product, the scale of advertising of the product and the price offered (bait advertising).
Bask in Barcelona for just €1!
Fly-by-Night Airlines is offering a special promotion on all our flights to Barcelona
This special promotion was advertised for one month in multiple magazines and on the Internet, but in reality only a small bloc of seats was allocated for the reduced rate. The majority of customers who tried to take advantage of this deal couldn't get a reservation.
The airline company should be able to offer a reasonable number of seats at the promoted price having regard to the scale of the advertising and/or (at least) put the number of seats available at the promoted rate.