It is not just about recruitment and retention, it is also about motivating the 4,500 pilots you already have to put a bit of extra effort in when required. 4,500 de-motivated and upset employees can do a lot of damage to the bottom line when the chips are down and they start saying, "No."
Having said that, why would anybody join a company where you know the terms and conditions will never be any better than they are on the day you arrive?