If this is indeed where AA or WN are moving, it may be a move towards implementing a PTO policy, which typically combines your sick, VC, and holidays.
If you currently earn 10 days VC and 8 days SK, plus 10 paid holidays, moving to a PTO bank would allow the company to position it as 28 days off per year. Sounds a lot more appealing than just 2 weeks vacation. Not all companies like the idea of closing down for a four day weekend when Christmas or the 4th of July falls on a weekend.
The downside... all those days will be used, or get paid out under most PTO plans.
The upside... most of those days will wind up being pre-planned for use, as opposed to the guy who calls in sick to go golfing, and if subject to bidding, they'll wind up being more spread out across the year.
Personally, I don't mind this approach. I've got 5 weeks off including holidays but not including sick days. This could increase it to 6 or 7...