I know the feeling! However, I have stopped keeping cardboard boxes because I will NEVER have that much stuff I want to mail. There's just something sooooo pleasing about the aesthetics of boxes . . .
I can relate.
@Ryo1 When my mother went into a rest home and my sister cleaned out her apartment, my mother had dozens of empty Kleenex boxes. However, she had flattened them and that ruins the aesthetic value. We had no idea what her plan was for dozens of Kleenex boxes. Now corrugated cardboard . . . that's a different story.