To become a really expert on something is necessary to expend a vast amount of time and effort. And those are limited assets in current life style. So much people is doing engineering to try to low the cost of being useful to the society (and become pay for that).
So using that scheme, people are competing again each others to became the a useful asset but trying to avoid the cost of time (so people can use the extra time enjoying life).
Other people just seems to be enjoying and playing with this time, eager to learn more even if will not become useful for another time.
Of course, things are not black and white and most of us are in the gray of being drived to be competitive and enjoy learning, but the two extremes lead to far different lifestyles.
The greatness of the playing way is that reward comes from yourself, is intrinsic, you learn more and more different things just because you want and you become satisfied, on the competing way your motivation is from outside and so it's harder to become motivated to continue the journey.