They're thinking that they're a monopoly and can do whatever the hell they want without needing to justify themselves?
To be fair they didn't. You can accept donations if you're an actual charity (like Wikipedia is). The line they drew isn't perfectly fair, no, but it's not a full ban hammer, either.
Now that I think of it, Uber has you put your credit card in. I'm not sure why that's allowed
Quote from policy [1]:
Developers offering products within another category of app downloaded on Google Play must use Google Play In-app Billing as the method of payment, except for the following cases:
- Payment is solely for physical products
- Payment is for digital content that may be consumed outside of the app itself (e.g. songs that can be played on other music players).
[1] https://play.google.com/about/monetization-ads/payments/
A donation doesn’t magically make everyone else work for free.
Yes, they charge 1/10 of what Google charges. The 30% has nothing to do with how much it cost them to run the service, so let's not pretend that they _have_ to charge them.
(I'm not saying they should offer cheap/free donations, I just don't think it's fair to talk about how much it costs them to run the service given that that's clearly not the driving factor)
Wait. I suddenly understand something I've seen previously...
There is a workaround! You simply upload two versions of the app, the free edition and the supporter edition. The support's edition is a paid app. You can ask the users who want to support you to install the paid app in your free app. The program itself is still 100% free and open source, there is no functionality restrictions in the free app, the donation notice can be turned off - just as a way to encourage donations. And it's nothing against the rules of the store.