This turn of phrase, which exists both in English and Norwegian (and probably in other languages (I assume this because I’m a privileged white male)), annoys me to no end.
Okay, so we have established that there is food in the kitchen, if I want any. But what about if I don’t want any? Where is the food then? Is the kitchen empty? Yes, I know the difference between if and iff, but it still sounds silly and illogical. Quantum food, Schrödinger’s sandwich.
It’s super common and everyone uses it, even I sometimes, though I try my best to avoid it. The problem is that most alternatives are more wordy and take longer to say (“There’s food in the kitchen, you can have some if you want”). Unambiguity has a price, and the alternative isn’t super appealing either. I guess I’ll just have to live with it.