Pilotchute
The high hour requirement maybe because of;
Insurance
Client Requirements
Auditor - you don't get recommended for contracts unless you crew have ###
and finally - the Owner who has a vested interest.
I know of a FOI who said it was illegal to require more than the CAO minimum requirements in an OM. He soon got the message that the CASA requirements are a minimum.
One company I worked for had a minimum insurance requirement of over 4000 hrs pic for a command on a Queenair.