Big difference in carbs for dry and tinned lentils.

I was browsing the supermarket shelves the other day and noticed that there was a huge difference in carbohydrates between canned and dry lentils. Napolina lentils state 10g/100g drained  weight, with fibre at 7.8g.

Consulting my "Calorie, Carb and Fat Bible", it appears that there is a big difference between the two.  Although drained, the weight is still mostly water, I suppose.  The drained tin gives 265g of lentils, 26g of carbs and about 19g of fibre, to give nett carbs of 6g. Too good to be true?