Granted, this time doesn't offer much benefit in the course of the working day, personally I'd find if I started work early, that sometimes the meat of my day really wouldn't be productive until later, even though I had been at work for several hours before productivity really took off.
When I had my second son and my wife stayed home for three months, I found myself spending most mornings going to the park with my children and wife and just enjoying the first part of my day with them. Each day I did this I came into work in the afternoon with a lot more energy and focus and finished the same amount of work, or more, plus I was able to enjoy my family and felt more fulfilled overall.
If I had started my day rolling groggily into the shop with coffee in hand and heroically pounding away, it would have taken me those same hours just to wind up into productivity, and my day would feel more tiring and unfulfilling in the end.
Honestly, 7 years in now, I've found I have a natural rhythm to my day, hours I'm focused, hours I'm tired, hours I just don't care and want to do something else, and if I try to work outside of this rhythm, it doesn't make me any more productive, just busy on my own time and needlessly braggadocios towards others when I can say I "worked" 16 hours yesterday when really only 5 hours had anything get done.
This is my own experience though, and to each their own. I tried all the productivity hacking and life hacking and it seemed for me, at the end of the day, that finding time to not work did more to help my work than working for the sake of work.