As a Plat with VA, I'm welcomed at both the gate and door generally by name (but I don't need to be, I simply need a smile). Occassionally there is a shadow next to me (but I won't whinge if it's not there all the time).
Do you (or anyone else for that matter) think that who you are/who you work for is somewhere noted on your profile, and this affects how you are treated? I have never (that I recall in recent times) been welcomed by name at the gate and rarely at the door. I usually fly J and just get the "row x on the right/left".
Regarding the difference in treatment based on age, we had a thread a while back about this... seemed fairly common. Not that makes it acceptable.