Why is it irrational and unproductive to try to "prove" or "disprove" the
existence of God?

It's not worth it.

Explanation:

I'm a believer, but if people are really sure to believe that they were created by the big bang, or by a superior creature they will believe it no matter what evidence you provide. Another example of this is flat-earth believers.

It would just be a waste of time, depending on your audience of course.  

 (A) Felix Longoria Affair

Explanation:  

Felix Longoria Affair is a social liberties association for Mexican Americans, to battle racial discrimination with political weight. The chief of the burial service home would not permit the utilization of the house of prayer due to supposed aggravations at past Mexican-American administrations and because of the fact that "the whites dislike it." Longoria's widow and her sister talked about the refusal with Dr. Hector Garcia, the author of the American G. I. Gathering. He, thus, reached the memorial service chief and got a similar refusal and method of reasoning.

And then in 1948 the remaining parts of Private Felix Longoria of Three Rivers, Texas, were recuperated from the Philippines, where he had been killed on a volunteer mission during the most recent long stretches of World War II.