Luxury is in the eye of the beholder.
Most of us, if told of a group who rub bird droppings into their faces, drink coffee made from beans excreted by cats, use bull's semen to wash their hair and eat cheese riddled with maggots, would assume that we were talking about the poorest of the poor. But, in fact, those engaging in these practices are more likely to be the super wealthy. And the reason is that, nauseating as such things sound, they are also extremely expensive, and therefore exclusive.
Of course those who engage in such rituals would deny that the expense and the exclusivity are the attraction. They would cite the aroma of the civet coffee, the flavour of the casu marzu (maggot cheese) and the complexion-enhancing properties of the nightingale droppings. And they might be right. But the wonderful thing is that the rest of us will be perfectly happy to allow such pleasures to remain as exclusive as they are now.