Why doesn't Twitch have their own donation system so they can take a cut of donations? Basically they need to implement StreamTip. They can then forbid partners (streamers who are allowed to have subs) from having any 3rd party tipping services. It's bad for StreamTip, but the profits for Twitch would be HUGE. There are some streamers, such as Lirik, whose main income from Twitch is probably tips. StreamTip already takes a cut of the tip, so it's not like the streamer would lose money if Twitch had their own tipping service.