Ryanair already have this down to a T. You don't actually interact with any ryanair staff from the time you book your flight until you're passing through the gate. At that point you meet the cabincrew/stewards for your flight, two at the door who check your boarding pass and glance casually at your passport, and you then walk across the runway to board the plane in no particular order. Everything is an extra,you're bombarded with ads for the duration of the flight (particularly annoying on a 45minute flight where they start at takeoff and keep going until you land). You also print your own boarding pass, and are normally located as far as humanly possible from the airport terminal, in an airport nowhere near the location advertised (London Stansted, Barcelona Reus, Paris Beauvais).

But I can fly to London return for 30 euro pretty much any time of the year in return for that.