Why I can use other people's copyrighted music:

Basically, this falls squarely under the "Fair Use" clause of the 1976 Copyright Act (17 USCS 107) and the Berne Agreement on international copyrights. I am:

For more information, see the Fair Use Test at the Copyright Website.

Note to the RIAA or its agents: I would welcome the free publicity that would result from a Cease-and-Desist letter, should you care to send one.