I wouldn’t say sour grapes, just that people have a certain budget. Forgoing Business/First i used to be able to afford more days away, maybe an extra city, etc
As I get older I take business class more, because I prefer the comfort over having a few extra days. Ask younger me and he would have taken the extra holiday days
You can sit in a fancy spa or a luxury hotel anywhere and they share a lot of intentional similarities to cater to the same audience of jetsetting luxury travelers. What does a plane ticket add to the experience over a staycation at the local intercontinental?
That is why it is very common for vacations (of people who stays at Four Seasons) to start or end a business trips: I am already there, might as well get my family to join and try some new foods.
As I get older I take business class more, because I prefer the comfort over having a few extra days. Ask younger me and he would have taken the extra holiday days