Actually, getting the ripped jeans gets you some extra dialogue and hearts with Luna. You do miss out a bit by being too frugal
That being said, money isn't too hard to come by. Just grind missions as much as you want, not like there's any time limits to worry about.
You do do realize that I actually played through the game already, right?

I've played through the full game like 2 times already, and watched several individual selected events multiple times already.
So no need to explain to me what getting Luna jeans with holes means (as to the results and dialogue), heh.
What I meant by frugal is MC's actual in-game personality.
The player can spot it in several scenes:
For instance in Luna's jean with holes event,
When MC looks at jeans without holes:
"The price is not too bad." (or something along those lines)
now, when he looks at jeans with holes:
"Why? Just why!! How is is the jeans with holes in them are soooooo expensive?" (also not exact wording, but something similar to that effect)
MC gives similar remarks when he buys items through other events also (like buying wine for Isabel, or buying the dancing clothes for himself with dance with Gracie event).
Game shows him to be quite frugal in mind (funny instances where Caterina & Amata looks at him with a sigh and shaking their head when they see him pick up the Ombra Soldato uniform in the Ombra contract

), even though he ends up spending money where he finds them necessary.