Flash (specifically, Actionscript) is an object-oriented programming language. While true, the end result is just a URL call, what this API wrapper does is provides a more straightforward and organized way of building out the URL. Flash generally is used for GUI interfaces, and this provides an easy way for a GUI to actually interact with the existing API.
For example, the person who wrote NabAIR is excited, because now they don't have to write a bunch of code to expand into new features of the API that they haven't included yet. Now they can just use my library, and concentrate on the front-end.