One could very easily discover on the amount people download if a certain user is a pirate or not.
though one could say "we watch youtube all day, and have a boy that plays warcraft all day and needs his interconnection broadband every day", one can easily see when large downloads go hand in hand with the purchase of large capacity storage devices or disks.
The majority of people buying large capacity harddrives (internal or external), containers with a large amount of DVD's (eg:100 box), etc.. generally are pirating.
One can say "he's a photographer, or records his own movies" probably applies to less than 1% of the purchases; so you still have 99% going to the stores to buy to satisfy their storage needs to store large sums of data.
Only a very few of them actually need the space (say over 100GB drive) or are downloading legally (companies excluded) and need the space for say:"Linux distro's", or "Video archive of the family, or holiday trips" .
Even the casual gamer which buys one game per month and prefers to keep their games on their system can choose not to install the full game. That way saving several Gigabytes of data.
A 100GB HD easily can store an OS and over 25 large games.
A 500GB harddrive more than octuples this;more games than one can play in their lifetime!
I know many try to defend the right to download, and thank God we can!
But it is true that illegal copying of information goes everywhere, everyone knows about it or at least knows someone who does it, even in the parliament. and that's probably why to today there's no real measure taken.
Because if there was, nearly half of the world will be in jail!
This includes those who happened to have downloaded a copyrighted song posted on someone's webblog!