Can atheists not be questioning? I suppose the truth of the matter is this makes them more agnostic than atheist and agnostics would argue that its not possible to prove a negative, hence to be an atheist is by definition not possible either.
Personally I have 'done' a lot of religion growing up, going to Church and two (yes two) Sunday schools every week, went to a Church school, been simultaneously a member of the Girls Brigade and a Brownie , a Sunday School teacher when 14, won loads of Sunday School prizes , own several Bibles ( won as prizes and still have them,) sang in church choirs, however no amount of this ' indoctrination' or whatever ,ever made me believe in God. At 15 I preferred Sunday morning telly to going to church. Programmes on religion but hey, I could stay in bed and watch them.
You could say that my atheism is also a ' faith' in that whilst it may be better to think of oneself as an agnostic, I firmly ' believe' that there is no God, no higher being, no heaven or hell. No evidence either way is required. We are simply here and now As Bugs Bunny would say, ' thats all, folks'.