Atheists Talk TV has a nice interview with Erick Jayne (James Zimmerman does the interview) regarding volunteerism and atheism:
One thing often lost in the various calculations about volunteerism has to do with what people do when they lead a thoughtful secular life. Various helping organizations are run by private non profits, often religious, and contributing to those efforts counts as volunteerism (if you do stuff) or charitable giving (if you give stuff). Fine. But in a world more oriented towards secularism, we would do more via the secular civic organizations at the local, state, national, and international level. When we pay taxes and as activists insist that some of that goes to “foreign aid” that, in theory, is like charitable giving but via a different rout that counts less than when a Mormon gives 10% of his or her income to the Mormon Church which then, in turn, uses that money for various things.
One of the problems that then emerges within the secular community is this: A certain percentage of atheists are also Libertarians, who don’t believe that civic institutions, ranging from the city that might make room for a community garden or a food shelf to the UN’s relief units, should be large, or even exist. I suspect that many of those individuals do not spent excessive amounts of time volunteering or giving money to non profits (prove me wrong if you like). They are therefore pulling back from most forms of helping each other that are used by much of the rest of society, including work and donations via church, non-religious non-profits, and civic institutions. That is not good.
I suspect, but can not prove, that all else being equal, the average person leading a thoughtful secular life tips more at the coffee shop than the average Libertarian atheist or the average religious person who pays a tithe. This is underscored (though in a purely self confirming non-data based way, I quickly add) by the occasional high profile event such as the pastor who stiffed the server with the nasty note on the check about how she gives money to god, why should she give it to some slob that brought her dinner. Again, I could be wrong about all this. This may be just me assuming that nice people are nicer than non-nice people, and being thoughtfully secular and humanistic is nicer. Nicest even.