that's a good argument :)
The first points to a node, the second evaluates to (say) the same node. But the second form is an expression; it is not so simple. To interpret it, we must know what node is, what i is, and that i and node are related by the (probably unspecified) rules of the surrounding program.
Nothing about the expression in isolation can show that i is a valid index of node, let alone the index of the element we want.
If i and j and k are all indices into the node array, it's very easy to slip up, and the compiler cannot help. It's particularly easy to make mistakes when passing things to subroutines: a pointer is a single thing; an array and an index must be believed to belong together in the receiving subroutine.