Nobody believes in nothing so everyone has a religion and is very religious. The question is who does people believe on or worst, what they believe on.
The issue is not that atheists do not believe in a living God, but that they believe on anything as their conveniently tailored, gods.
What this result on is the confrontation of selfishness versus love with the believers on anything on the side of selfishness because what they believe on must be oriented towards their own egos, their own gain, their own pleasure.
It is inconceivable to have a person without a living God, the one and only living God; to be capable of expressing true love because after all love is giving selflessly and without expecting anything in return.
Hate is not the opposite of love, selfishness is, as peace is not the opposite of war but just embracing the truth, the absolute truth and not something constructed to satisfy pride, ego or hedonism as mere relativism.
There is therefore not much to be understood about these people in the 20% of the equation and in fact, I would dare to suggest that it is much more than that because people nowadays tend to forget their creator to choose the path to hell because it appears to be more appealing to that suggested great majority.
The answer to this is not in statistics but in the hearts of each and every person, who needs to seek on his/her own for the truth. For the purpose, enough has been showed to us and we should be able to see the truth before us, from the bible, the Ten Commandments and from the teachings of Jesus, only Son of God made Man for our salvation, as recorded in the Gospel and the truth about the Sacraments.
The big problem of our days is that relativism wants to take over and while Christ asked us to deny ourselves, take our cross and follow Him, these new found 'sect' pretend us to deny the truth and our humanity while keep our selfishness going and throw our crosses to everyone but ourselves.
The real issue is therefore selfishness versus selflessness, absolute truth versus relativism, good versus evil, the confrontation that has gone on since the beginning.