Many intelligent, very successful people consume it and you would never guess.
Just curious: How many do you know who are married (i.e., to someone of the opposite sex), go to church, and have more than two children?
Due to the legal issues, people in most places will never admit it unless it is in private with very close friends. They also hide it from their children because a child mentioning it in school will invite unwanted attention from the gestapo.
People that have several kids are very busy will partake much less than people that dont. Just like responsible people with kids drink much less because they simply dont have time.
In places where illegal, I know 4 couples that meet your criteria and partake occasionally (1-2 times a month). About 20% of those that are close friends and meet your criteria. They are all financially very well off so they have more opportunity to relax than most people with 3-4 kids.
In places where legal, many more admit to it. Id estimate about 30% of upper-middle class (and above) couples with children I met admit to occasional use. I dont have too many close friends where its legal, so the actual number is probably higher.
For equally financially successful married people with no kids, the percentages go up to about 30-40%. For unmarried financially successful men, it is easily 65%+ that smoke occasionally. For unmarried women, maybe 30%. The women tend to be the reason the men quit. Women just dont seem to like it as much.