DQ, you're convincing. I see what you're saying. I've lost the proper perspective because I'm so used to my current situation. A sexless marriage seems kind of "normal" to me, while a sexual marriage seems like what newlyweds do. The kids hear Jay Leno joking about how the woman has a headache, etc. Or his joke about the true story with the woman who wanted sperm to be extracted from her husband who had just died in a car accident. Jay joked about the irony that only after the guy died was the woman interested in his sperm.
People "get" these jokes because sexless marriages are more or less the norm. Or so it seems to me when I don't give it much thought.
So in that context, I really have a hard time seeing how it matters so much what the parents do in the bedroom. I think my kids all know my wife has a "headache" all the time when it comes to sex, totally in accordance with the "norm" established by the Jay Leno jokes. Sure, the kids might realize it could be a little better, but I don't think they're running around feeling like their life is a fake sham just because mom has "headaches" with dad.