Overly focused on calorie tracking

I started my weight loss at the end of January this year, currently down just over 12kg (109kg - 197-something). I've joined a few subs and I don't understand the focus on calorie counting. Surely just some basic knowledge of the overall energy value of various foods, along with an idea of what constitutes a reasonable portion size should be enough to get it right?

Also, shouldn't most of the foods we're eating in a day be either negative calorie or close to it ie vegetables? I eat mostly veg and salad, minimal fruit (due to sugar content) and add in protein in the form of lean meat, hard cheese and nuts. I limit carbs to one slice of multigrain bread a day and a small amount of noodles/rice or half a small potato with dinner. I've lost this weight without ever having the need to weigh or measure anything, let alone the relatively minuscule amounts of oils and fats used in cooking.

What am I missing here? It may be down to me just having a fairly routine diet, it's easier for me to eat the same foods throughout the day every day and just vary the evening meal.