You can't, because people don't pay and don't want to pay, unless they are forced to, as in there's actual scarcity (i.e. no way to easily get that content from anywhere else).
Clearly it can work, because it works for Patreon. It also works for twitch, who allow people to "subscribe" to streamers they like. This entails paying $5 a month (half to the streamer, half to twitch) to receive exclusive chatting rights, special "emotes", and other non-essential features. People do it not because they want access to the special features, but because they want to support the streamer. It seems that people are adverse to paying only when it is on an-item-by-item basis, but are not adverse to it in general.
Why do you think "you can't", despite Patreon (for now) looking like it can work? (Although they of course don't have to finance an entire music sharing service with this)
Music fans seem comparatively loyal and willing-to-spend to me, so I'm curious about your reasoning.
People will pay for indie music, it's been happening for a long time. It still happens today. Particularly if, as we've been talking about here, it's focused on electronica/hip-hop people will pay so they can perform the track in public. There's a real stigma against playing stolen music like that. Plus you can pay for higher quality versions. Lower quality versions don't sound as good when timestretched so they dont work as well for mixing.
Maybe a limit on how many streams/month that could be lifted for a certain fee?
Regardless - point is I think there are ways to monetize this enough to keep it running. I doubt any streaming service will ever be a cash cow but I'm sure there are ways to keep them running.
Scarcity is part of Patreon. I'm guess/assume that much (most?) of the support comes from backers wanting exclusive content that is sometimes offered as a reward.
You've lost me there.
You can't, because people don't pay and don't want to pay, unless they are forced to, as in there's actual scarcity (i.e. no way to easily get that content from anywhere else).