So - previews, listening to it on the radio or pandora and renting something from netflix is a "try"
And if you want to posses it forever - you "buy" it . . . just like everything else in the world that's a product or service which you purchase.
That being said - I have napster. I pay a few times a year ($15.00) and I can listen to all the music I want - and if I want to make a portable copy *then* I can use my earned credits - no extra money off the top - which is 15 credits per cycle . . . and if I want to exceed those credits I have to pay per song.
You can't convince me that somehow owning music or movies is a right - and so it's your right to take it just because you don't want to spend a little bit of money on it or you don't feel that artists who are sharing their talent and gift with you don't deserve their fair cut.