I think Apple would have made their case more convincing if they offered the AirPods free of charge. I find I use my headsets while charging very often and I think not having that flexibility is a real bummer. In addition to carrying around an adapter that will most likely get lost. I can imagine the moments:
*Just got done taking a bunch of pictures, snapchats, etc.. while travelling and now I'm on my flight back home. My phone is low on battery so I'll plug it into the charger while listening to my audiobook. Oh wait... can't do both
*Driving with a friend, want to show him/her a new song. Sweet, their car has an aux connector! Oh wait..
*At a friends party, want to play some songs. Oh damn, left my adapter at home.
Apple really needed to do more to make this transition better. They are taking a huge risk here.
Its like marrying a girl you just went on a first date with. Yes, you know you'll probably spend the rest of your life with her and she might look really pretty, but as we all know you can't just jump in like that.