I've seen many poker rooms who offer free chips like pmavens and also have ability of chips transfer. BUT most of them only allow users to transfer chips IF remained amount not get less than free chips portion.
For example if site is offering 1000 game chips for free every one hour and a user has 1800 game chips, he can only send 800 of that and not more. this way they don't open multiple accounts to gather lots of chips for free.
- Also it is more practical if you put a charge for transfer. (for example %2 of transferred chips). this would be very beneficial for administrators.