Just because it has resources to manage doesn't mean it is a resource managing game.
D&D is a narrative game first, a strategic boardgame second. (That is why it is an Role-Playing first, Game second)
The point is to create awesome stories and memories with friends at the table. If this involves spending resources on frivolous shit, then so be it.
I'd bet you will remember stupid shit that Wizard got you in longer than when you tactically defeated a boss.