What will you get by buying your airplane ticket with bitcoin everyone on forum are saying don't sell your bitcoins just hold it the price will increase in future and stuff but what are you doing by using bitcoin in a coffee shop or buying a airplane ticket just selling your bitcoins and doing that wouldn't make you great like how that guy felt by buying pizza with bitcoins. Seriously man why do you want to bitcoin as fiat just keep it like a investment.
I don't see any problem about bitcoin used in such things, it is a digital currency. As a currency online, it is inevitable that it may be used for this payment, there are news about bitcoin being used in reserving rooms on a hotel or paying tickets for an airplane.
In the future it will be used in many offline transactions where wifi or bluetooth are just the needed connections to make it happen. Whether it will be happening or not, we all know that the idea will be surging in their minds.