It is just too bad that Google's implimentation of IMAP and folders ***** so bad. They really are not folders, but rather labels. So your entire email box is just a large flat file that takes an application set up to read those labels and interpret them as labels.
Everyone is blaming Apple, but if you look at Thunderbird, Outlook, etc, they all are doing that same interpretation of labels to come up with the folder structure.
Then you're stuck with this other folder called [Gmail] that has the basic folders you see with the web interface, but really are more like "smart folders" in that they are just custom filters for the labels.
Gmail has become this large beomoth of a web application and Google only cares about one thing, it looks good in a web browser.