It isn't clear that having non-miners using 1 of 10,000 chains is good either. It means you can't transact with someone using one of the other 9999 chains without an intermediary.
- Usually you are not transacting with all people in the world (if you are not world wide spread corporation and you have office in all regions).
- 99% of your transaction are located in your town (quarter).
- I think you are not interested in collecting and verifying all transaction from China or Russia, USA, EU
=> 9,997 chains are irrelevant for you. You only cares if number of bitcoins is same .. less than 21,000,000 and if chain holding your coins is valid