1). More mellow  you start to be less bothered by the little things as you get older.(unless its a SO).
2).  Normally willing to spend a little more money.
3).  I have heard a few time that the younger guys are to full of themselves and expect oohs and ahhs.
4).  Ya I think the kids age might have something to it.
5).  I also think we really do feel grateful they are there for us and express it better.
Funny though as I bet most of us see younger women than us. Of course this is just hearsay and speculation.