I have been a regular member of 3 types of Christian denominations (Baptist, Pentecostal, Methodist) and attended services in perhaps a dozen more.
The one defining feature I take from all my church experiences, including Bible study, is a lack of emphasis on intellectual fulfillment and a focus almost totally on emotional/spiritual fulfillment. That is not necessarily a bad thing in and of itself, but I hypothesize that it has to do simply with the economics of running a ministry. If a preacher delivered sermons or a teacher lead studies that did not appeal to some sort of common denominator in their community then the church would simply not survive. DEEP discussion and understanding of issues, especially when they cross over into science and the level of outside understanding you need to have a meaninful discussion, are left out of the main focus.
Also, it is not the main mission of the church. They don't care why you believe as long as you believe. The first job of any church is to ensure the salvation and baptism of all the congregation and that is drilled home every single Sunday.
What good would talking about evolution denial do in terms of saving that person at the end of the pew or at the other end of the table?
If a nation expects to be ignorant and free, in a state of civilization, it expects what never was and never will be. --Thomas Jefferson