Lots of people go to Christian churches that aren't even christians. It is naive to believe that everyone who claims they are a Christian really are. If a person went to last year's Mardi Gras and did a poll, most of the attendees would have listed their religion down as 'Christian'.
In many parts of the country, especially in the bible belt, being a christian and going to church is not about faith, but just part of the culture.
Jesse Jackson, Al Sharpton and Bill Clinton go to church too and they are hardly examples of moral character.
Your knowledge of Evangelical Christianity is zilch.