At the time I thought but what about all those people who record their own music or videos on those blank cassettes? They'll be forced to pay rich corporations for the privilege of using those items to record their own original material. Of course the issue went far beyond that, and it would still have been thievery even if people were using those cassettes only to record and copy existing music and films.
Now we are still dealing with this corporate/statist monster, especially with the internet. Big corporations care nothing of free markets or liberty, and they would willingly have draconian laws enacted to stifle the free flow of information online in order to have big government act on their illegitimate behalf.
For artists, of course, the whole thing is asinine and short-sighted. I saw a wonderful video on Leonardo da Vinci and his inventions on Youtube. It featured background music that fit it perfectly, but later the music was removed by the video creator due to a "copyright claim". The music I had not heard before, and I was immediately interested in finding it and hearing more from the artists. If I was producing music, I'd want it distributed and heard by as many people as possible, but the music industry prevents this through their alliance with the State. They are the true destroyers of creativity and artistic expression.
The real pirates and thieves are not ordinary people using and downloading already existing music. The thieves are the fascist corporate interests, whose whole enterprise would not exist in its present form without the backing of the oppressive and evil entity called the State.