It might have been budgeted in or part of some other discretionary spending limit (employee perks, parties etc) and this is so small that it doesn't matter.

I have seen termsheets where the founders need board/investor approval for spend over $XXXK, so that it stops/limits misuse of capital.

This could have been board approved, if it needed to be or else investors/boards can always ask for it to be returned and mandate approval for future spends above $X in categories outside of regular business spending.