I think it all comes down to priorities and choices.

I have friends that have scraped together and borrowed in order to fund a J ticket and also sacrificed the quality of their hotel; to them the difference was worth it. If I was in a position where I had to choose, I'd pick a cheaper flight class in order to book a better hotel, better excursions etc.

Additionally, to echo Fitch, I have a friend who is comfortably in the top 1% yet does not travel in cash booked premium cabins for long haul (outside of business travel). For him, it simply doesn't represent good value, regardless of whether he can afford it.

I don't whether an individual can easily afford, or has to stretch to afford premium cabin travel is necessarily indicative of whether they book such ticket types.