OOC - some examples would be nice :)

I think a lot of the people that fall into this camp (at least those that I know of) are people that have just recently deconverted - they've just been through a major life-change involving religion and therefore are understandably entranced with the whole process as it is particularly meaningful to them.

Alternatively, they are reacting against some heavy prejudice that they have had to suffer through - or have some loved ones that are particularly "afflicted" and want to see something done to prevent it happening to others.

Sure, there are other big, important things out there... but one man's meat is another's poison, and all that.

I think it's easy enough to say that there are bigger problems out there... when we are looking at it from the perspective of having been atheist for a long time. but some people have just had their world cave in - everything has been upturned. They no longer have that huge big safety net underneath them that tells them that everything is going to be alright in the afterlife. Maybe they've just discovered that they've been wasting one seventh of their life in church when they could have been out there exploring his beautiful world that we live in or spending quality time with their kids... it may seem like nothing important to you, but it's a Big Thing to some people.

PS - I am also inclined to agree with you that there are better things the time could be spent on... but that's "better from my perspective" and it's not mine that counts.