I think a lot of people expect this to be the way it works, and perhaps it should be, but it's not the way business thinks. They see it as you volunteering free labor and that's pretty much it.

There is some research showing that coming in early makes your manager rate you higher. But it seems unrelated to number of hours, ironically. http://qz.com/209513/no-matter-what-the-boss-says-about-flex...