Personally I've never known anyone who is completely free of carbs.
However I know that when someone actually eats no carbs whatsoever, their body makes what is needed by way of gluconeogenesis. themedicalbiochemistrypage.org/gluconeogen
Those white carbs (and others) you mentioned can be detrimental to your health if they are consumed in excess, since they are addictive they usually are consumed in excess. They’re also the main contributors to health problems such as obesity, diabetes, hypertension and others.
With low carb you lower the risk illnesses; you’ll also likely experience improved mental concentration and dental hygiene, reduce muscle and joint pain, control headaches and prevent gastrointestinal problem. If you restrict carbs and eat CLEAN you’ll suppress your cravings and overcome emotional eating.
I love my fruits and vegees, I even know those that follow the paleo eating style who are complete vegetarians, see their delicious foods: pinterest.com/martic24/vegetarian-paleo/
. Although most following the paleo style are meat eaters :-)