Why is this the answer?

The answer is nut because this riddle is a super fun way to describe the tasty snack that is hidden inside a hard shell. This puzzle uses clever, imaginative words to make you think of a real house and a real piece of meat, but it is actually talking about how a nut is built by nature. Let us look closely at the first part: "A little house full of meat." When you find a nut like a walnut, an almond, or a pecan, it is protected by a very tough, outer covering. This hard covering is what the riddle calls the "little house." It is a safe and strong home for the seed inside, protecting it from animals and bad weather. The part that the riddle calls "meat" is what you actually eat. It is the crunchy, delicious kernel inside the shell. This edible part is packed full of energy, vitamins, and a yummy flavor. So, the shell is the house, and the seed inside is the good stuff that is waiting for you. Now, let us think about the second clue: "no door to go in and eat." If you want to go inside a real house, you just turn the knob and walk through the door. But a nut is different. Its house does not have a door! The shell is completely sealed up and locked tight by nature. To eat the tasty kernel inside, you cannot simply open it like a box. You must use a tool called a nutcracker, or sometimes just your strong hands, to break the shell and crack it open. That breaking is how you finally get in. That is why the riddle says there is "no door." You have to break down the walls of the little house to reach the hidden treasure. The whole riddle perfectly describes the little journey you take just to get to the delicious, crunchy nut.