I seem to be a bit lost here- are these what you stated?
you left your wallet in a seat on a plane
it was taken by a sub-contractor employee of AA
the person was caught
and AA offered some compensation and you are not satisfied
and you feel your forgetting the wallet is similar to baggage and AA should apologize....
hmmmm
Welcome to FT - any opinions of writers (including mine) are not legal advice nor are we able to issue policy for airlines.
My opinion is you deserve nothing from AA and should be more than satisfied.