Your comments

I agree with this, but my suggestion is that you simply are allowed access to Gringotts in addition to the Hospital Wing when fainted. Thus you can withdraw enough money to un-faint if you so wish. I feel it is indeed a bit unfair that you can't un-faint even when you do have the money, because let's face it; who has been walking around with 200+ galleons in their pocket since Gringotts was added?