Yes. if you had stood in the rain as soon as the game started, Boruto would have found like $7, which is enough to afford the snacks for Himawari on day 1. and if you did not do so then, you miss that scene. You cannot make it up later and just buy snacks any old time. You had to buy those snacks then... think of it like. there was a super special limited edition snack in the store then, and you missed your chance to buy it because it wasn't there later.
Just to see that one scene. But you have to play the game again in both love and hate routes to see all the games content. You can just make sure you get it on that play-through to unlock it.
I suggest you join the discord or go to the website in order to get the guides. it'll walk you through step by step the beginning of the game to get the Himawari fly incident scene.
Yoruichi has one 'secret scene' too that can only be unlocked during one of her quests and is possible to miss.