ARTS ONLINE They Buy all the Albums, but Trade Concert Bootlegs By MATTHEW MIRAPAUL Marc Daniel added 1,400 albums to his compact disc collection last year. But he is not waging a campaign to reverse the music industry's declining sales. Almost all the titles he acquired, by groups like the Grateful Dead and U2, were live concert recordings that were never officially released. Nor did he buy them in record shops. Instead, he used the Internet to trade for them, swapping copies of his discs for recordings he desired. He said his CD trading with its questionable legality and exhilarating...