Freedom of speech
The letter to the editor is the forum we all get a chance to voice our opinions. The proper response is to write a rebuttal to his views. The newspaper prints letters based upon the market they feel they are catering to. Sometimes they print letters representing the minority so as to rile up readers and spur more paper sales or interest in the paper.
Don't let it bother you. 99.99998% of the planet doesn't have a complete or accurate view of life, evolution or cosmology. That's a lot of people to get angry at.
;-)
SDAI-tech1