Trying to argue with high profits by speculating that they might have made even more? At best you are arguing that they don't need copyright protection because they are doing just fine without it stopping piracy. And I would agree with you.
But there is a more fundamental error in your argument. You are, in fact, begging the question. That is, you are relying on an unproven assumption that there was in fact more money to be made. That is bad enough to end the case, but your unproven assumption is also wrong.
Money is not an unlimited resource. In fact, each person has a fairly limited quantity of it at their disposal. So the only way that the MAFIA could possibly have made more money is if it had been allocated differently. For example, if instead of spending $50 to go to a theater I pirate the movie and it at home (using resources already funded) and put the money into savings instead. By the MAFIA argument I would have just stolen $50 from them -- but unless I never spend the money it is really just a deferred expenditure.
Of course the reality is that no one does what I just proposed. In point of fact, people have fixed costs that are required for living (rent, property tax, groceries, etc.) with the remainder being disposable income. And, immediately or later, that gets spent. And it gets spent on luxury items, whether that is a beer you drink at home (stealing money from a bar by not drinking there), going out to watch a movie, eat in a restaurant, etc.
Now, there is room for some shuffling here. Perhaps Peter prefers eating in restaurants while Paul prefers watching movies. From a strictly economic perspective there is no difference between the two, whether or not none, one or both engage in piracy.
People make financial decisions as to whether or not they can afford to see a movie or fly to the Bahamas for vacation, but piracy is not a financial decision unless they are paying for it. And the Internet connections are a sunk cost: you pay for the connection whether or not you are downloading music and movies. The absolute closest you could get would be a claim that higher bandwidth connections are absorbing the displaced cost of buying a movie. To demonstrate the lost money would require identifying (or at least having a good approximation) of how much money was spent on upgrading Internet connection speeds for the sole purpose of piracy.
The bottom line is people aren't upgrading Internet connections to enable piracy, and even if they were the amount of money is so small compared to how much money the MAFIA grosses that it would not significantly alter the outcome.