Zinnia Jones says:
Atheism is not a kind of theistic belief, because it does not involve belief in any deities. It’s actually the absence of such beliefs. Similarly, atheism is not a position based on faith. Instead, it is a lack of faith. We don’t have faith that there are no gods, we just have no faith that there are any gods. Simply not believing in gods does not involve any kind of faith, because it does not require taking a position that is unsupported by evidence or contradicted by evidence. We just find the reasons given for belief in gods insufficient and unconvincing. Faith is not necessary in order to not believe in something that there is no reason to believe in.
YASHWATA 
This -atheism is a belief as well- is an argument I hear too often. Even from people who are non believers.
Mostly I use a simple example. When your friend has a hobby, like stamp collecting and you do not collect them, then it is quite weird to state that the absense of stamp collecting is in fact a hobby. It works quite well.
Great website by the way. I found it today and I think it is very refreshing. Thank you.