the low fat yogurt scam

Around here yogurt is an essential part of the daily meals, usually there's 3 types of yogurt on the market at the same price, low fat, normal and high fat. the. it's the same for milk as well.
it's all good and I guess there are people out there who really think by eating low fat things they can lose weight. my problem is that low, high and normal fat yogurt and milk are sold at the same price while most of high fat ones are from pure milk and the other two are just watered down.
they are selling us tap water at the same price as milk... I saw where yogurt is made, they don't have devices to take the fat out of milk, even if they had, the result would be the same as diluted milk. milk is lactose and fat particles suspended in water, remove some fat and you'll end up with a higher water to fat concentration just like adding more water.
so the next time you're faced a choice to buy different kind of yogurt or milk at the same price, go for high, eat less of it each meal and save some money.