How does the seller hedge against currency risk? Given that BTC is very volatile and that it can be difficult to get USD or whatever currencies the carriers are accepting for tickets the reseller ( Cheapair in this case ) has to be able to ensure that they are getting tickets for an amount in BTC greater than the cost of the ticket in the target purchase at the time they ( Cheapair ) purchase the ticket from the airline. If they guess wrong and they charge you 2 BTC for a ticket to Malaysia, but the ticket would cost 2.6 BTC by the time they confirm the transaction with you and start buying the ticket from the carrier... they'll probably just refund your BTC and tell you to try again. If on the other hand your tickets would actually cost 1.8 BTC by the time they talk to the carrier; you paid too much.

Also nobody is going to sell you an anonymous airline ticket so, the benefit of using Bitcoin in this case is very dubious.