Also, compare clicking on various Menu Bar items (or other UI features) with option-clicking on the same item. Apple has advanced little mini UIs all over the place.

Similarly, look at many current System Preferences panels in Mac OS X. The basic stuff most users need is up front, and the rest is hidden behind an "Advanced..." button.

I conclude that having an advanced mode, or various enhanced features accessed in different ways from the standard UI, is not inimical to Apple's approach or UI philosophy.

Not the best example, but the OSX calculator app seems to have this.

Aqua (GUI) and Terminal (CLI)