Another reason...
if a BAW plane goes tech, they'll get another one onto the apron ASAP. If a RYR goes tech, you get a grudging refund and lose your holiday!
If the load factor on a RYR is too low, they'll cancel the flight at short notice. Tough luck!
If a BAW has to divert, they'll pay for a bus to get you to your destination. RYR? You guessed it...
and don't forget about the rather creative city descriptions for the airports!