The lack of recognition of any cultural norms got my attention too. I believe I remember JR once mentioning a watch that Sue Ellen got him for Christmas, but I believe that was it. I can’t recall any mention of popular music they liked, any holiday, or anything of that nature, and aside from one of the first five episodes, it was always summer. I believe Southfork decorated for Christmas with a big tree would have been nice.
As for not going away if you owned a property like Southfork, I agree with that a hundred percent, but a lot of people like to use their riches for Yachts and such, but the Ewing’s just seemed to enjoy making money fo the sake of making it and not necessarily to spend it.