We live within 1.5 hours of several major airports. When I go, I either drive (and pay extortionate parking charges) or go by public transport, which is also pretty straightforward, and cheaper if I'm travelling alone.
Most of my friends seem to be regularly doing airport runs for their adult children, often in the early hours.
I'm not saying I wouldn't do it, if I was asked, or it was necessary, but it's occurred to me mine have never asked.
Hopefully that's because they prefer to be independent, rather than they don't feel they could...?