Of course eating isn't a one-off option, but it's highly unlikely that anyone will be using income from this to make ends meet. Mirroring the tip analogy offline, I don't go into my favourite restaurant and tip the service staff there every week, even if I haven't eaten; it only happens if I eat there. It seems to me that one-off tips will be a heavily requested thing at least.

Great idea, I hope it really takes off.