Yes. ANY source of sugar (glucose, dextrose, malts, fructose, lactose, etc.) is considered a net carb or "sugar" if you are counting them. The reason is that any source of sugar -- even fruit -- is turned into the same thing once you eat it and it causes the same biochemical reaction in your body.
Just as an example, a cup of grapes has about 60 calories and 16 grams of carbohydrates. Of those, 15 grams are sugar. That means 58 of the 60 calories comes from sugar. That sugar turns into glycogen in your stomach and goes into your blood stream of "fuel." Your body then produces insulin to tell your cells to open up and use this fuel for energy. The insulin also tells your body to stop using fat and to store fat if the cells have more "fuel" than they need.
While there are certainly vitamins and fiber in fruit, that doesn't negate the fact that fruit is loaded with sugar. People who follow a paleo or Keto diet rarely eat fruit, and when they do it is more likely to be blueberries than an apple or banana. Eating three servings of fruit isn't a lot of calories, but it will definitely cause a blood sugar increase and the resulting release of insulin to deal with it.