When a culture rejects God's Word and worships idols, they will start a downward spiral that leads to immorality.
Romans 1:27-28 And likewise also the men, leaving the natural use of the woman, burned in their lust one toward another; men with men working that which is unseemly, and receiving in themselves that recompence of their error which was meet. And even as they did not like to retain God in their knowledge, God gave them over to a reprobate mind, to do those things which are not convenient.
I read about this first on Voddie Baucham's blog. It seems that among the Pashtun men in Afghanistan there is rampant homosexual pedophilia. You can read the article here:
Afghanistan's dirty little secret