When it comes to describing an unnecessary luxury, the possibilities are endless. One might call it an extravagant indulgence, an unwarranted excess, or even a frivolous expenditure. Synonyms for this phrase might include opulence, extravagance, lavishness, and superfluity. A more modulated term for such excessive indulgences might be a mere indulgence or a frivolous purchase. Some might use adjective such as excessive, luxuriant, or decadent to describe these extravagances, while others might use phrases like superfluous spending or ostentatious indulgence to convey the same idea. Regardless of the terminology one chooses, it's clear that excessive luxuries are something to be avoided in the pursuit of a serious, productive life.