"Many people have little difficulty opening up their laptop and forgetting the rest of the world for an 8 hour stretch"
I haven't come across anybody who can in-the-zone code a straight 8 hour stretch during the daytime (nights are obviously very different). I'd love to hear from people who've managed to do this.
Anecdotes about how "hardcore" people are in this regard usually wind up being worthless. 9 times out of 10, when I ask someone about an "all-nighter" they just pulled, it turns out they actually stayed up until 4:30 and slept until 9.
I expect most people who talk about how they can stay locked in the zone for 8 hours, in reality take breaks for coffee, browse the internet, and break for lunch.
(There's nothing wrong with taking breaks!)
(1) Me. Just now.