Sorry I didn't read the book but I am curious if there is any scientific evidence to back this up.
Humans are very good at pattern recognition and we're optimized for it. Real calculation takes time and energy and might make us less able to survive.
Sometimes that grass moving strangely is just the wind..sometimes it's the tiger, the ancestors who sat down to have a good think about it got eaten.
When I was younger and played chess my teacher drilled into me that when you find a good move that's the time to look for a better one, we instinctively play the first 'good' move we see, in fact manoeuvring your opponent into a trap by giving them an obvious 'good' move is effective against people who don't play a lot and very ineffective against people who do (and even then vastly stronger players than I ever was still fall for it occasionally).
What Kahneman is talking about is a tendency for the brain to swap out expensive slower analytical thinking with cheaper and faster heuristic thinking. Both ideas are only tenuously related because they both discuss the role of the brain's glucose metabolism.