Plane Sailing
Astral Admin - Mwahahaha!
Now that you mention it, you're probably the "some DMs" I'm remembering.
I don't quite understand what you mean about the NPC age/profession chart. How do you transfer the PC's spending of treasure into a standard for NPCs?
I forget the details but it was something like
Peasants spend 10gp/week (equivalent)
Townsmen spend 30gp/week
Nobles spend 100gp/week
After giving an arbitrary starting age of 16 at 1st level, I could see that a peasant fighter who was 3rd level and needed (say) 4000xp would have taken 400 weeks to reach that level, and would thus be about 24 years old. The noble fighter who was 3rd level would have only taken 40 weeks and would be about 17.
A 40 year old peasant could have spent his way to 13,520 xps. A 40 year old townsman could be at 40,560 and a 40 year old noble at 135,200 xps
I made a little chart with level along the top and social class down the side, and the intersection gave me an approximate age.
Not all NPCs would have spent the maximum amount, but (especially with the way the xp charts went in 1e) it was quite possible for nobles to be 'name level' NPCs, although it almost impossible to "spend" their way past that.
Cheers