I have a dual-screen setup with my main monitor on the right, so the left-handed, fixed menu really is a pain: either I make it collapse, and then have to target a very slim pixel-wide bar to un-collapse it, or I have to leave it there and waste screen space.
My setup at work (software engineer) is what you described: dual-screen, main on the right with the windows start bar collapsed on the left side so it's in the "middle". After quickly getting used to targeting the pixel-wide bar instead of heavy-handing the cursor to one side I found the bar was in the ideal place to be reached quickly from either monitor. That's my personal preference.
But I agree, I don't see why the menu location shouldn't be customizable.