If they were smart, they'd charge a dime or a nickel a song and let folks put it on pay-pal. If they offered high quality, they might get some folks buying into it. Some of the rips on free swap sites are just horrible.
I buy CD's, as the MP3 format just rots my ears. Even CD's are sometimes tough to listen to, as the digital encoding and digital delivery takes much of the life out of the recording. It's like tin when you finally hear it.