It's kind of the same idea that if you are leasing a car but don't drive it you have to still pay the monthly lease fee, if you leave your home for a month or two and go to europe, you would still be required to pay your monthly mortguage fee. you are paying for an actual service from fido to be made available to you, not for the actual consumption of usage on your phone, This would have also been explained to you when you signed up, otherwise if you disagreed with it, you could have chosen to sign up for a Pay As You Go service instead?
