It would make more sense, you are correct, to consume food in a simple manner. However, no man is Willy Wonka, and no man can live on candy, so it is currently unthinkable. Astronauts often life off of a similar idea of food, however. Nutrient-packed, vacuum-sealed foods that are mashed into pastes and can last an extraordinarily long time, if memory serves me as well as it generally does.
Food is not always about merely consuming nutrients or "refueling" the body, truthfully. Food is a grand part of culture and heritage, something my people have passed down since creation, and something that can be very wonderful or very disgusting. Cooking is a good thing to understand well and to perform regularly, particularly if you live alone and cannot afford to eat out every day, like myself. Fast food is not really food in its purest regard. No, food is about flavour, drink is about complimenting it, and dessert is about the end of a good meal and sweetness to finish it.
I can show you what real food is like, and you can taste as much as you'd like. I'm sure those extra 25k molecules are dying for a work out!