This kinda manga tends to do that only when it's not an adaptation. LN series very often get the relationship started in the first few volumes before going SoL with the couple.
And Haruka is always bankrupt because he's the one financing those purchases. Moving money from one hand to the other doesn't pay his suppliers and his trade with the mushroom-addicted woman only brings in so much cash.
The revision was already accomplished in the companion title when we got her POV on alla dat. TLDR of it all, she was just really clumsy about how she presented herself (in her head, anyway). Doesn't make it any better when Saotome only has her words and actions to go on, but it's not really...