Why do record labels spend so much on marketing to the younger demographic with the lowest disposable income instead of adults with a larger disposable income?

The recorded music industry likes us to cry that piracy via P2P has led to the decline of their business. However “wallet share”, or the proportion of disposable income devoted by people to purchasing recorded music, started declining back in 1994, well before the internet and the onslaught of file sharing. Even by 1994 this “Wallet Share” had still not recovered from the highs of the late 70s, whereupon it declined after the death of disco. And yes, competing interests of the video – and now DVD and games sectors – can be noted as serious competitive constraints, especially games in terms of the younger demographic segments.