Your closing premise is one of Socialism and Humanism ideology, which can be embodied by both Theists and Atheists.
Is the intent of your question to ask if atheists are too focused on their belief that their is no God?
If so, then, of course, they are NOT too focused on such a belief because that is all that the subject of Atheism entails.
If you think they should discuss Socialism or Humanism, then you are merely asking them to change the subject.
They certainly can't "sell" the idea of Atheism better by wrapping it in political ideologies, because people of all religions already embrace those same ideologies.
The atheist is being honest by discussing their belief that their is no God.
Although I disagree with the Atheist's belief, I prefer their honest approach myself.
Many Atheists agree with me on social issues, so what?
That doesn't make me an Atheist, nor does it make them a Theist.
It just means we share some common ground.
I bet they like to eat food and drink clean water too.
Should we discuss that too, instead of our belief, or lack of belief, in God? Of course not.
There is nothing wrong with Atheists focusing on the issue of "God".