How about putting it down, Ed? Your antagonistic comments of that nature only denigrate the site. I know you have the ability to be civil and would kindly appreciate your being so. Not trying to be offensive, so pls. refrain from throwing a gauntlet my direction; I'll not pick it up.
Back to the OP's concerns.. date conflicts unfortunately occur everywhere from time to time. One simply has to choose and go forth. Politely expressing your disappointment to both venues might propagate a better dialogue between them in the future, or not. I do think it important to let both know that you were forced into choosing when it was your intention to shoot both.