With the numbers given those are the ages of the people who can receive as part of the elder people which we call senior people would like to retire at that early age if they can but it depends on the kind of life what they have, if you raise already a good amount of money during that times you can now leave as you want and retire but what if not? people in the lower-low status of society can't choose this kind of life because they don't have any options they need to keep working so they can serve food every day and keep working hard for the challenge of life. Not all the time government can sustain those seniors at the end of the day it's their path of their life that make them keep alive.
Not many people can achieve the level of income that will allow them not to work when they want. Also, often the pension is not enough to provide themselves with everything they need and these people have to continue working.
Sometimes people continue to work even in retirement because they are bored of being retired without work, but this is also a very rare case, most often they keep going to the work because they need money. The retirement age is needed so that the government knows when to pay citizens a pension, but recently there is a tendency for governments to raise the retirement age, so people have to work until they are old.