From what I understand, it's somewhat common to take these tests and be matched to people you may be related to through Ancestry or similar sites. The one negative with the circle DNA kit is that uploading the DNA data isn't possible to other sites, so you're missing a part of that experience which you'd get with a cheaper test kitAnd the whole thing is fairly gimmick-y and imo very different from researching actual ancestors for a family tree, so I can definitely see posh rich kids do these tests (whereas like you said, actual research to build a family tree is probably something middle-aged/older people are more interested in)