The issue has arisen due to the people who are detirmined to get around the traffic management that was put in place. It wasn't the 1TB per month that was the issue, it was the 1TB per month at full speed, avoiding the traffic management that was put in place to avoid it negativly impacting the network.
Sure, Telecom could probably spend thousands of dollars (probably tens of thousands of dollars) trying to find a fix to the problem but I guarentee you that as soon as they do someone will find a way around it and we are back to square one. Why should Telecom continue to waste money because of those who abuse the system?
You could also argue that my anti-virus should know in advance exactly what virus's are going to be coming out in the next month and already have a defence in place but it doesn't work that way. No one has a crystal ball to figure out what the unscrupulous people in our society will come up with next.
But if anyone does find a way to predict the exact course of the future I'm quite sure there are many companies out there who would be interested in speaking with you.
It should also be noted that Telecom is one of only a very very few providers out there who provided a truely unlimited data plan. At least they tried where no one else is.