I think the line between "luxury" and "proper" is the debatable point.
And yes, no doubt some people use that as an excuse to over spend. But that doesn't mean people don't take it to the extreme in the other direction as well.
It really does come down to the numbers. If I can spend $X to take in $5x over the month, you should do that.
> If I can spend $X to take in $5x over the month, you should do that.
indeed, but the point was that the $5x is not known in advance, and in fact, might even be an emphemeral figure.
Buying the right chair and desk for your height is not a luxury, but buying something expensive, when a cheaper version, which would've done the same job, is available, is to me the definition of luxury.
To be fair, whether or not the cheaper version would do the same job is also not known in advance. There's also the fuzzy edges of what it means to "do the same job". All chairs ostensibly "do the same job" of providing you somewhere to sit. But there's variance there.
Just like all turing complete programming languages do "the same job" at some level. But we'd all be more productive in your choice of high level language over any processor-specific assembler.
Then it becomes a matter of asking when does it transition between appropriate and luxury. Which grain of sand makes the pile?
And yes, no doubt some people use that as an excuse to over spend. But that doesn't mean people don't take it to the extreme in the other direction as well.
It really does come down to the numbers. If I can spend $X to take in $5x over the month, you should do that.