I doubt manager, chairman (person?), or president will become last names.
You're missing an important point: those last names came out of the
practice of naming people by profession, ie- John the Archer, Lars the
Smith, and Tim the Enchanter :)
People just dropped the 'the' after awhile.
It's one type of common naming techniques.
Others-
animals- "john Bearclaw"
actions- "john runner-over-water"
descriptive- "john redeye"
parental- "john ericson" < "john eric's son"
clan- "john O'Henry" < "john of the Henries" (mac and mc I assume are
similar, but from Gaelic)
professional- "john carpenter" < "john the carpenter"
numeral- "john unthirtu" < "john 132"
Oh, sorry... numerical derivations haven't occurred yet... ;)
- -Me
[Pooh Bear incarnate.]