I came here to say the same thing : C# makes it intentionally very difficult to create a global variable, and the first example is just a case of sloppy coding, whatever the language. You cannot develop a habit of creating global (or undeclared) variables if you're coming from a C# background.

Similarly, the global namespacing - a C# developer is going to look for ways to declare namespace.definition style, and is not going to spontaneously come up with namespace_definition, as this is an unseen pattern in C# examples and general practice.

Perhaps it would be a good primer for a VB6 -> Javascript developer, but I don't imagine there are too many of those around.