As fucking bizarre as it seems, many people really do not count liquid calories. Either they genuinely don't know that liquids contain calories or they deny/underestimate just how much shit they're drinking. I had to explain to my old carer that the reason she wasn't losing weight, despite having a very healthy, calorie controlled diet, was the fact that she was addicted to strawberry milkshakes and yoghurt drinks. You rarely saw her without one or the other in her hand. She was drinking well over 1500kcal a day and had absolutely no idea that "it counted".