I’ve played other games with guilds and alliances and they have different “tiers”: competitive, casual, just for fun, that kind of thing. I think they could implement this when searching for alliances so people know what they are getting in to. If alliances are straight forward with expectations, then people know what is expected of them and won’t have to worry about getting kicked. Obviously a “competitive” alliance will have more expectations than a casual one and people can choose based on their level of play.
But I agree that alliances should have the ability to see who is donating either way. What they do with that information is up to them.