I lived the same "realization moment" last year talking to a friend.
I was saying that I need to go home to wash my white undershirts as I only got blacks left (small t-shirt to wear under a shirt and not freeze to death during winter).
He asked me why so I have several colors of undershirts.
Well, black and grey for black or dark colored shirts, white for white or clear colored shirts otherwise you’ll see it behind the fabric, duuuh, are you dumb?
The answer:
Or you can wear white ones under dark shirts as well and it won’t be visible…
🤔🤔🤔😧 FFS dude, why did I never thought of that?