I think the important thing is to keep Spotify from being the only way you can stream music. While I agree you can buy discs or digital downloads, these are fundamentally different methods of consumption from streaming.

Stopping Spotify purchasing the exclusive rights to stream prevents a monopoly where, if you want to stream, you are ‘forced’ to use Spotify and pay/listen to ads there. Keeping artists’ options open allows the most customer-friendly streaming service to win out as consumers choose which streaming service gives them the best product to listen to who they want