Why? Ray Charles can see the number of atheist libertarians around here. Not all libertarians are atheists, mind you. Not even close to all. But the most anti-God, anti-religion, anti-Christian posters are those atheistic libertarians.
The number of atheistic Libertarians was not the matter of disagreement. Neither was the possibility that some may have made anti-Christian posts. However, your initial statement was:
"...there are quite a number of libertarians on FR who never miss a chance to trash and denounce both Christians and Christianity."
If this is true then it shouldn't be too hard for you to provide a few examples to support your accusation. However, I should point out that disagreement with religious dogma, or opposition to government funding for its advancement, does not constitute denunciation or trashing.