It's his own fault.
He obviously knew he was going half a terabyte over, it's his own damn fault. He knows cogeco is going to charge him for every single bit transit over their network. Anyone who thinks otherwise (like this person) is a moron.
Also, half a terabyte in a month? That's WAY TOO MUCH for a residential connection. If he's transferring "project files" or doing any other type of work using his internet connection, he should be subscribing to a commercial package.