Your "brain" has a picture of what reality is. If you are used to a 10000ft runway in front of you, even if your plane needs 3000 ft to stop, you might tend to have a long landing in order to make F3 exit, which is more convenient. And on a day-to-day basis, when you arrive on this particular and legal 3000ft runway at minimum width, you will be not as "easy" as you could be , if it was your home field.
i think that what it is meant for short-field experience ( i.e. on the limit of the AFM, and the associated regulations)