Let's say each person in your community has 1 resource unit. They are 10 peoples in community including you.

Each member of the community can either consume 1 resource himself or give it to a fund that distributes resources to those in need in third world countries. Each resource consumed by one of you brings him 1 unit of happiness, but each resource given to charity brings 5 units of happiness to some third world resident (he is poorer and needs more). For each of you, the happiness of others is 10 times less valuable than your own happiness.

F u t i l i t y = R c o n s u m e d i n y o u r c o m m / 10 + d o n a t e d R * 5 / 10 + R c o n s u m e d b y y o u

Thus, it is preferable for each of you that everyone else donate their resources, but you consume your resources. Also, everyone prefers a joint donation to a joint one consumption. In the absence of coordination, if each of you consumed its resource, and you will all receive 1.9 units of utility, which is much less than 5, therefore, you need coordination.

Thus, each of you is interested in others donating money, and he is not, but at the same time everyone prefers joint donation to joint consumption. In the absence of coordination, each of you will consume your resource, and you will all receive 1.9 units of utility, which is much less than 5. Therefore, you need coordination.

So how can you coordinate your community?

Option 1: you can gather a few friends who are interested in effective charity, tell them the idea of this article, and then declare that if at least one of them refuses to donate to charity, then you will not either. If each of your friends also agrees to promise that if someone does not donate to charity, then they will not either, then each of you have not option [everyone exept me donate to chatiry], so you will choose between [everyone donates to charity] and [no one donates to charity]. If your friends are altruistic enough, then everyone will choose to donate, and you rich good equilibria.

Of course, the more people there are and the less altruistic they are, the less chance it will work. If you decide to arrange such a donation with 10 people, but 1 of them will be selfish, or he simply will not have money, then he will refuse, and you will not receive anything. In general, this option is good for a few friends, which is not bad, but it will not be able to scale.

Option 2: make donations of some percentage of income a prerequisite for staying in the community. For example, your football team may agree that anyone who does not donate 10% of their income cannot stay on the team. Staying in the community is a reward, the ban on staying in the community is a punishment, and punishment can be used for coordination.

This option works well when the community is stable, and it is difficult to just leave it (everyone still has the motivation to ensure that they do not donate to charity, but that others donate). If for most of you a football team is about friends, community, and an emotional connection, then almost no one will leave it just to avoid donating to charity.

This option is very sustainable, because most people are happy about the existence of such a community, and at least they will not make coordinated efforts to change this rule.

This looks like a rule that can be established even at the level of national communities. For example, the church X in country A prohibits anyone from staying in their community who does not donate 5% of their income to Fund F.