Is it good for strong and healthy person to sleep all day, while others are working?

It is NOT good...not at all, and that's a great Proverb!

If they are a night shift worker it is.

Sure! Why not sleep and relax while others toil? Be proud that you have no work or craft. Enjoy the world that others have created for you. Then explain it to God.

No, not unless the person was working a night shift. Strong, healthy people have the ability to get up. Or else it is just laziness.

If a strong and healthy person is sleeping all day long, then I am afraid to say that the person really is not as strong and healthy as you may think. Normal people get out of bed in the morning. If one stays in bed all day long and sleeps the days away, something is wrong with them. Most likely depression, I would assume.

No. Eight hours of sleep is about the maximum that most people need. And if anyone sleeps during the day it probably should be because that person is doing something else at night, like working.