People are highly irrational creatures. If you ask someone whether it’s fair for a person to do nothing all day having their work done in an hour, vs a person who takes a full day to do the same work, they’ll probably say no. They might say it’s ok but they’ll feel the person with all the time on their hands should be doing SOMETHING. The fact that both people are doing the exact same amount of work is irrelevant since one is doing nothing and relaxing.