Often Christian culture and biblical truth are not exactly equal. There are many pieces of Christian culture which are simply culture and not necessities.
That Christian culture exists which has no basis on necessity in scripture is fine, as long as it is not normative/absolute as Christian culture sometimes is treated.
You see going to or supporting Christian movies is not a biblical necessity. I for one have never gone to or supported many Christian movies because I do not find them to be helpful.
For those who believe in these things or find them of use that is fine as long as they understand there is no necessity for these things. They fall in the realm of adiaphora (things on which Christians are free to disagree).
Christian music also falls in this realm. A Christian need not only listen to Christian music as many churches suggest explicitly or implicitly. Again it is choice which exists in the realm of adiaphora.
Christian culture is fine as long as it does not produce judgement on Christians who do not accept or appreciate the elements of Christian culture. The elements are not biblical necessity and as culture can freely be rejected if one in good conscious does not find them of use.