Naruto, like Kakashi doesnt see anything wrong with it. He brings small snack packs on missions because, as everyone knows, he is always hungry. After a decent fight with some low-level bandits on an escort mission (Kakashi sat out, swooping in only to protect his pack from critical hits. He's still their teacher and they have to learn somehow) Naruto whips out a snack pack.
Sakura, in an attempt to bond, asks oh so politely "Hey Naruto, what snacks did you pack? Smells almost like jerky." She takes a step closer, ready to receive a small portion as Naruto always shares with her (but only reluctantly with Sasuke).
"S'Beef Bites with brown rice and blueberries and fish oil from Northern Salmon. Better than the previous stuff I was getting." Naruto (and Kakashi) think nothing of it as he passes over a few pieces.He's actually quite proud - and grateful to whomever upgraded his kibble stash. It tasted better, he stayed fuller for longer, and it kept his wallet fat. He knew this brand was nearly twice as expensive as what he usually got and used real meat chunks rather than the by-products of the butcher shops. The bag that appeared on his kitchen table was a welcome treat, one that had been pretty reliably delivered every few weeks.
Sakura pops a few pieces in her mouth, crunching down with anticipation of a burst of delicate flavors.
Immediately she spits it out, coughing and spitting out what she can. "By the Sages, Naruto! Is that dog food!?"
Naruto, a little defensive now, nods. "Its well rounded for nutrition and doesn't taste that bad!" He protests. "If it's the beef flavor you can't stand they have a white fish, a chicken and-"
"You can't eat dog food Naruto! That's for dogs!" Sasuke says, eyes narrowed and lips turned down in disgust but also concern. Was Naruto having money trouble? Kakashi was their sensei, he was supposed to help them if they were. But it didn't seem likely? Naruto had been balancing a checkbook since they were in the Academy!
Kakashi, not seeing a problem with his choice of snacks for Naruto, eyes his other students and takes a handful from Naruto's snack bag. He activates his mask genjustsu, lowers his physical mask, and pops the handful of kibble pieces in. No, still tastes just as good as the last time he had that flavor. He looks down at Naruto. "I don't know what they're talking about, Naruto, this tastes delicious."
He takes a few more pieces, and then replaces his mask. He looks at his other two genin. Maybe it was something you had to start young? The dryness of the kibble did go better with water, or even better, milk, but surely it wasn't that bad.
Sasuke and Sakura looked at each other. Was Kakashi telling then to back off of Naruto's eating habits? That he was aware of his situation and was addressing it? He knew Naruto got defensive real quick so maybe he was trying to prevent them from embarrassing the little blond. "O-okay, I'll take your word for it." Sakura said. "It's just not something I would pack for a snack." Sasuke nodded in agreement, eyes narrowed at their other two teammates.
Now everytime Naruto whips out his snack packs he shares with Kakashi and the other two look on in horror and confusion. It makes for an awkward campfire dinner sonetimes.