1- I'm not sure why someone would change their name in an effort to keep it, but either way there is still some effort put into saving the name in compliance with the current naming policy.
2- Flagging the account doesn't solve the issue of name camping it makes it easier to tie up 1000 names just by logging in to play your main.
3-Now you want them to open a whole new server and incur the additional costs just so people can camp names easier?
The current policy is fine as is, and doesn't require them to spend any more of their valuable time/resources coding a whole new system.