It matters when comparing to cinema tickets. Let's say a ticket is normally $10 for the sake of a nice round number, and they charge $30 to get the film at home

It matters when comparing to cinema tickets. Let's say a ticket is normally $10 for the sake of a nice round number, and they charge $30 to get the film at home. If you want to watch on your own it's expensive, on the other hand if you have 3 friends over to watch with you then they have lost $10. Obviously it's not quite that simple, as some of those 3 friends might not have gone to the cinema - but maybe they all would have.