"Unnecessary or wasteful" is as subjective and context/environment-dependent a judgement as it gets.
Other than that, the sometimes toxic dynamics of sudden windfalls in funding have also been discussed here at length: Paradoxically, not spending investors' money can sometimes be considered worse than wasting it on moonshot projects (or even outright on fancy office furniture and eye-catching employee perks).
I work for a startup that raised a bunch of money and hasn't spent most of it. It might have seemed bad last year, but I'm sure their investors have come round to the idea now ;)
Other than that, the sometimes toxic dynamics of sudden windfalls in funding have also been discussed here at length: Paradoxically, not spending investors' money can sometimes be considered worse than wasting it on moonshot projects (or even outright on fancy office furniture and eye-catching employee perks).