But my idea of an enjoyable holiday includes the travelling, because I also really love flying (I know on MN you are supposed to be gripped with terror the whole time, but not me!).
Me neither! I have enjoyed most of my flights in economy (funnily enough the only bad experience was when I upgraded my seat, but then Wow Air always were diabolical). I only gave the hotel example as an example - I'm not fussed by 5* hotels, but most people were giving examples about physical comfort and eating well.
I wasn't even arguing against it, really. Just pointing out that the reason this expense is so polarised is that the difference between doing it normally and doing it expensively is vastly more than the usual difference between the basic or luxury spends.
Like a day trip out for example - you can often pick an ok trip for £100, and a premium version of the same for £150.
Or a hotel might be vastly better for £50 extra/night. Or a meal much nicer for £20 extra.
The differences are usually in the 10-50% range. Whereas for business flights it's easily 100%+ extra, if not 3-5 times the cost.
It's not about whether or not you enjoy it, it's the weight of difference compared to other upgrades.