Why do Agnostics not care?

To me the whole God issue seems like a pretty big deal. Not to be offensive or anything, but why do some people just not care? I mean doesn't this belief change how you live your life? If you will constantly be afraid of an allpoweful hand that could smite you if you sin. Or if you can party and be awesome and have fun without a care about such things.. Sitting on the fence.. isnt that sorta defeating the purpose of choosing.