Crew costs are irrelevant to the closure of MAD. Airport departure tax from there (& BCN) will increase from approx 11 to 28 euros per passenger in 2013. Most passengers won't pay the extra 17 euros and those that do may see lots of empty seats around them. Since the profit per passenger is less than 17 euros per flight I don't really see any point in LCC's operating out of MAD (or BCN) at all
.