What exactly do you mean by atheists talking about spirits? Like using the term 'spirit' in a sentence? I mean in that regard, an atheist would just recognize that a 'spirit' in the traditional sense of a soul would be nothing more than an artifically false construct of man. However, if an aeithist wants to boosts someones moral, then using the word 'spirit' in a different sense would obviously mean they're talking about something else other than the soul.
Hang on, can't one be an atheist and believe in spirits? It's 'a-theist', not 'a-spiritist'.
True, although atheism in its most common form tends to align itself with a naturalistic perspective - which technically would preclude anything like ghosts for example. Of course how that works out in practice is another story.
For example, I know atheists that swear they have seen ghosts.
Indeed, there was thread here about how one study showed that atheists tend to be more superstitious than theists. It was noted for example how superstitions didn't die out in the Soviet Union, despite officially being an atheist country. At least within the Abrahamic religions, superstitions have been continually condemned.