Thanks guys, and thanks Eric for the explanation.
I have another question which relates to web assist files placed in your site folder when using the extensions. I actually signed up for the subscription plan the other day and and it looks like the include files are placed in directories at your site root, named after the extension you use.
Is there a way to define where all extension includes are placed? I.e can specify /includes/ as the place where all web assist folders are created?