Believe it or not, among wealthy countries America is the most altruistic: The World Values Survey asked people how important it was to them to serve others. The following is the percent who answered "very important":
Percent saying serving others is very important to them:
Puerto Rico 78.8
South Africa 49.2
Saudi Arabia 40.8
Bosnia and Herzegovina 17.6
The regional pattern: East Asia and SE Europe, low; Latin America, Muslim, and African, high; and developed countries, moderate. It's interesting that an altruistic spirit has little to do with how well a country actually serves the needs of its people. The service-oriented nations in the list generally do a poor job. In fact, Japan and Korea--the last two on the list--have produced successful societies without a strong feeling of duty to others. Western countries have created high levels of well-being with only very moderate amounts of altruism.
And while the United States has the reputation of a gang of heartless capitalists, it ranks as the most service-minded country among developed nations.
I can examine this more systematically when I have finished building a data set, but these patterns might reflect the religious culture of the people. The Catholic Church may have taught Puerto Ricans to believe in the importance of serving others, even if they don't always do it. On the other hand, Japanese people might be good neighbors, even though they don't have the same kind of religious culture.