I can understand why people may feel cooking is unlocked too late, but my personal take is that unlocking cooking earlier would mean significant changes to gameplay. Having this recipe for the cookout kit at level 9 makes it a small addition to the game, making it an early unlock would make it a big shakeup to some people's strategies. As much as people may want that, I just don't think that's the intention here.
See, I usually have upgraded my house to have a kitchen before Fall Year 1, and not because it gets me the kitchen, but because I need a kitchen before I can get married. I can't see how getting access to cooking any earlier would change much as far as my gameplay. I would still be working with the same ingredients and have the same recipes, because I'm still processing the same stuff and making friends and completing quests at the same rate, not to mention that Queen of the Sauce doesn't give recipes any faster than 1/week.
And to be honest, carrying one of these around so I can cook outside the house? It sounds like a pain in the @$$. Not only do I have to have this thing in my inventory, but I have to have all the ingredients of the thing I'm going to cook in my inventory? Am I bringing this stuff along with me? That's a lot of inventory space occupied by, frankly, a bunch of otherwise useless stuff. Am I bringing this all in the mines so I can cook something while I'm down there? No. I'm cooking it before I go into the mines. The food takes up less space than all the ingredients plus the campfire. Am I foraging and have a lot of wild tree seeds I'm going to make into a field snack? Don't need a campfire. Am I mining and have a bunch of bug meat I want to make steaks out of? Don't need a campfire. What other ingredients am I finding on an adventure that I'll find the need to cook it up on that adventure? Nothing. Literally. Seriously.
IMHO, the only reason to introduce the cookout kit is to cook before you have a kitchen because cooking outside the house once you have a kitchen is pointless.