Well unfortunately this is how it is in the real world as well.  If you are solo mining with 20 Antminer S3s you need to pay for their electricity every day but you only get income when you find a block.

If ghash.io is having a bad luck spell then they still need to pay for the electricity despite not making any income - hence the continual fees.

Having said that yes it is assinine that customers should be charged that high a fee unless ghash.io were to mine with $0.50 electricity while mining in Beverly Hills, CA... but the customers chose to buy that hash...

I would suggest selling and taking your BTC while you have the chance.