Bertrand Russell, a great British philosopher and mathematician once wrote an essay "In Praise of Idleness." I don't exactly remember what he wrote in that essay, as I read it a very long time ago, but I do feel that mention of that essay is appropriate for subject in hand. I am going to discuss about the 'leisure' and its role in shaping thinking.
As happens with anything, it tends to make good thinkers better and bad thinkers worse. Being idle, as well as getting enough of seclusion is indispensable for thinking thoroughly. I don't suggest that there are not people who could think well in market place or while carrying out their routine jobs. I just intend to make a suggestion that for special purposes, it's important to have privacy and idle time for thinking well.
Ancient western thinkers have stressed it that only aristocratic people are well suited to do philosophy. It seems reasonable, because unless you are free from loads of earning a living, you cannot devote your time to philosophize. But it seems to be the only half-truth. Our apelike ancestors who had hunter-gatherer existence, did not become really great philosophers, even when it's almost a given that they had enough of idle time. (This was recently mentioned by a fellow interlocutor in a discussion.) Why? Because it takes a certain degree of aptitude to think through things and even aristocratic people are not all inclined to Philosophy. Are they?
Ancient thinkers used to think that aristocratic oligarchy which is driven by Philosophy is best rule for any state. In the heydays of renaissance of Athens this idea of philosopher-rulers gained some good popularity, but Socrates, who belongs to that time, was a commoner. Socrates is considered as father of western Philosophy. Similarly, Nietzsche, Heidegger, Kant and Hegel were not aristocrats. They were all greatest philosophers of their times.
As far as eastern Philosophy is considered, people from all walks of life have contributed to it. Ancient sages used to live simple lives with noble thoughts and Buddha, though born to a royal family, lived life of an ascetic. The eastern Philosophy is mostly a Philosophy of mystics and ascetics--in search of Truth and Being. Ascetics indeed have a lot of idle time to think, in fact, they don't have anything else to do, because they live on social welfare.
In absence of righteous timely triggers, idleness will always induce boredom in its subjects, which is root cause of all evils and random thoughts coming from Noosphere, when level of awareness is very low, in absence of life-force-energy, lead to more evil; therefore idleness should be taken with a pinch-of-wisdom, if it's to reinforce original thinking and Philosophy.