Your definition of "lifestyle" and mine are a bit different. As I have stated before, in the studies I have read on this topic do not support your whole assumptions. An average of doing something once a month is hardly a lifestyle.
Children do not need to be told the details of anyone's sexual life, to see and experience the fruits of a chosen lifestyle. The child living in the crack house does not need to be told the details of drug use, to experience the results of that lifestyle.
Ok, now here is where you really lose me, yes living in a crack house definately has adverse affects on all living there, however, your attempt to draw a parrallel between growing up surrounded by people shooting up, and the fact your parents go out once a month, are completely different beasts. Even if the parents during that time do engage in sexual activities outside the norm, I fail to see how you draw a conclusion. It seems to me that you definately have a preconcieved notion of the typical swinger not based on research but on Pornography.
There are a variety of reasons why swinging parents attempt to hide this lifestyle from their children, they know it is extremely difficult to instill values of commitment, loyalty, faithfulness when they live the opposite.
Ok, now stop right here... this is where you REALLY are out of line. Commitment, loyalty and faithfulness cannot be instilled by persons who engage in sex acts outside of their primary relationship? Well if that is true at least 70% of the people walking the earth will never understand those concepts. Your assume first of all that the marriage involved vows regading sexual relatoins, which is not neccessarily the case. Number 2 you assume that simply by the fact the couple for whatever reason chooses to engage in sexual activities with others that they are not loyal or committed to each other... as though simply because they have had sex with others they will walk away from their spouse or family... This is a HUGE leap of logic. Divorce is no higher among swingers than the general population from what I have read, in fact I believe it is slightly lower.
It is fairly well known and established that children who are aware of multiple sexual partners with parents, often experience emotional problems, as well as feelings of betrayal and anger. Children do not like to be very different from their peers. If they wish their children to be involved in a religion, this lifestyle is in opposition to most religions.
Again we return to the question of a parent exposing a child to their sexual activities. Since we both agree they should not be exposed to the details, why do you then condemn those who deviate from the norm for exposing their children? IF they don't expost their children because it is ADULT in nature, you condemn them for hiding it.. no parent should be talking about the intimate details of their sex life with a young child, no matter how wild or prudish their sex life may be. I personally believe more kids have found out their parents were having sex with others through finding them cheating than finding them swinging... but I suppose that isn't important either.
There are a multitude of reasonings, but the bottom line is that swingers DO attempt to hide their lifestyle from their children. Monogamous couples do NOT attempt to hide their lifestyle from their children.
Again we return to the lifestyle question, I suggest honestly that your impression of the typical swinger is quite skewed. Just as the average homosexual is not down in soho with 25 partners or more a night, the typical swinger from what I know is not either. I fail to see how as I have said, a couple going out once a month is a lifestyle, or how the activities they engage in in those adult settings away from their kids somehow adversely affects their family lifestyle. Pick up some human sexuality studies, you might learn a thing or two.
I further stated that there are often events in a life that are not typical of the lifestyle, such as the urban professional spending a week in the Alaskan wilderness.
I suggest that you use the dictionary of your choice and look up the word, "lifestyle". You will probably disagree with the dictionary as well, but nevertheless, the English language is composed on standard definitions, and not opinions, or what we would like to see the word mean.
BTW, where did you come up with the "once a month" swing thing, as pertaining to the Van Dams?