Strange! Sadly I don't remember the experience of learning about scope myself (I was too young), now I find it hard to see the "mind state" that makes it hard to understand.
Isn't it a feature of natural languages to have the same word assume different meanings depending on where it's used? The concept translates nicely, and in PLs it's completely explicit whenever this happens.
That is an interesting thought: although, it is something that non-native speakers struggle with when learning a new language. I wonder if that is a factor when learning a new computer language/concept too.
I suspect it is also related to the Curse of Knowledge (https://en.wikipedia.org/wiki/Curse_of_knowledge). Once you are past the hurdle of initially learning a concept it makes it hard to imagine not being able to grasp it: especially when dealing with abstract concepts such as scopes.
