Your paragraph regarding Pink Floyd is eerily reminiscent of the Payola scandal of the late 1950s and early 1960s. Even Dick Clark was investigated, although it was assumed that he wasn't directly involved in any of the shenanigans himself. In its own way it was the music industry's Watergate. Yet I don't know the names of any of the key players who were taken down. Perhaps some book was written about it at some point.