I would hazard to guess its due to two things:
1) a lack of understanding about how the machine works, and in particular the way the memory is organized; and
2) lack of explanation of why anyone would need to use pointers. Introducing pointers in the context of a linked list, or explaining call-by-reference would probably help make things more concrete.
I have friends who had to take an intro to C++ as their first (and only) programming class.
I heard them talking about passing arguments to functions as "call by reference" many times, and it was obvious they had no idea what they were talking about, just regurgitating what the instructor said.
