Originally Posted by
stevenh92
Quite simply, it's easier to defend your resources on their own than it is to defend your resources and your town hall. Its impossible to protect both sufficiently. Therefore, you can use more protection for your resources rather than using any to protect your town hall.
Secondly, when an attacker destroys your town hall, they instantly gain one star and therefore a win. This awards them with the league bonus and you get a nice 12 hour shield. This helps to protect your resources when your offline. So having your town hall outside of your base increases your chances of getting a shield.