Despite the claim that all that exists is the material world, atheists will almost always point to the things that aren’t material as why life is worth living.Maybe you're inexperienced in understanding this form of meaning, since you attribute your meaning to a more objective, eternal thing. I maintain that impermanence does not make something meaningless. It doesn't have to last forever to have meant something to the person living that life.
I'll be real; you're coming off as pretty judgmental and short-sighted right now. It takes a lot of arrogance, even cruelty, to tell somebody the meaning they derive from life is meaningless. Are you being any better than a militant atheist right now?
So in effect their actions do not match their beliefs.
