I think the fact that his wife had just had their third baby adds a bit to that weird feeling for me because the contrast between how their evening/night looked like probably could not be bigger. I do not expect him to sit still sipping wine, I do not know what his agreement with the wife is, and the situation caught on vid could be entirely innocent, but I agree it could cause speculation that is not necessary or that could potentially fuel gossips that will than live their own life.
On other note, I know guys who behave perfectly and noone would suspect they are unfaithful but they are sleeping around cheating and the ones that are naturally affectionate and all handsy and flirty with women that are not their partners but it does not mean and does not lead to anything more. So I guess you never know. On totally different note, I also have a friend whose husband had a side chick for more than 10 years and she never knew but all people in their work knew and did not tell her. She learned of the affair when the side chick got pregnant and gave this guy an ultimatum so he decided to divorce.