Somtimes it's morally important to recognize that someone may inappropriately and irrationally be offended by something you do. It's worth going the extra mile to prevent their offense, even if that offense stems from something silly. Other things are more important than the little amount of effort it might take to avoid that offense.
But aren't there times when giving in to stupid reasons for offense is catering to dangerous trends and opening the door for complete abandonment of careful thought? Perhaps a good example of something that stupid would be asking Santas to avoid saying "ho, ho, ho" for fear of offending women who think you're calling them prostitutes. There are enough serious worries in this world about people using terms that are actually offensive to women that putting serious effort into telling your employees this kind of thing just seems like a waste of time.
What's worse is that this trivializes the kind of language necessary to address real social ills. This kind of warning insults anyone who has actually been called a ho (and in fact all women, since all have been subject to blanket descriptions of all women as hos). If you can't distinguish between real misogyny or sexism and something that no reasonable person could take as anything but innocent, then your moral priorities are so twisted that I'd rather not have you giving moral recommendations to anyone.
Update: Snopes debunks this. The reason had nothing to do with confusing the sound "ho" with the U.S. slang for prostitute but just to avoid such a deep, booming laugh. But this strikes me as harder to believe than most of the stuff coming out of Snopes, bedause another report from Australia later that week had someone actually getting fired for exactly these reasons, and I thought the source for that was pretty reliable (not that I remember it now).