OS X does the same thing. It has a launcher on which you pin the most used apps and for everything else you need to search it with Spotlight, or go to the Applications directory in Finder. I haven't seen many people complain about the usability of OS X in this regard. IMHO, the Start menu is a broken abstraction.
As for the UI and that bullshit on being optimized for tables ... I actually like that Unity is so space efficient. For example, why in the world would I need a window top bar, if the window is maximized? Vertical space on 16:9 screens is precious, Unity optimizes for it and I find that to be awesome ... like, one of the reasons many people like Chrome's UI over Firefox is exactly because of this, yet Unity brings this design decision for all apps.