If you buy a yacht or a supercar you give the money to a number of people. If you actually burn the money you destroy it and it is lost for everyone.
So while people do what they want with their money, actually burning it like is rightly seen as a dick move by most people. It is also illegal in many countries.
Is it lost for everyone or is it more like a stock buyback? Did everyone's money become 0.000000001% more valuable by taking that chunk out of circulation?
But if you go deeper in the meaning of money, it's even better: when you receive money, what you actually receive is an IOU for a good or a service. E.g. when you receive $40 for fixing a computer, it means the society owes you $40 that you can claim at any time. Burning the $40 means that you fixed the computer for free, and that you don't want anything in return, and at the same time nobody can claim the $40 in your name (i.e. you didn't give the money away).
The "you should buy anything to move the economy" is a well known economic fallacy.
The point is that in real life (as opposed to an academic textbook) burning those $40 does not do anything useful or positive to anyone, while spending them or giving them away to someone would do something useful.
Not an economist, but in crypto, "coin burns" are a regular occurrence where a percentage of supply is destroyed, typically by sending to a public address for which the corresponding private key is proven unknown.
The result is intended to be a rise in price, benefiting all holders. It can be uncertain to assess whether a resultant rise in price is actually due to a coin burn, but given a coins supply is commonly used as a valuer, it's plausible.
So while people do what they want with their money, actually burning it like is rightly seen as a dick move by most people. It is also illegal in many countries.