(re: Swapping and the Weezer Idea) All the Weezer stuff is legal. People (as far as I can tell) aren’t interested in swapping the albums. Weezer has released tons of demo recordings on their website in the past. Those and live shows are mostly what gets traded. They definately don’t care about the demos, there has never been a problem with the live shows. The only gray area is b-sides (from overseas). Technically these shouldn’t be traded, but I don’t think they care about it since actually purchsing an import single (especially older ones) can be difficult.
They’re a pretty fan based band. The reason all the demos got released online was so fans could vote for which songs to put on their fourth album (Maladroit). Groovy.