Maybe they will get lucky and find the shortest route and they can feel good about their work. There are students who need practice with reasoning skills. Answering these questions can help a student extend their thinking. There are students who need to be challenged with something new. This seemingly innocent problem could be used as a doorway into the area of Discrete Mathematics and the study many different algorithms.
Some students even discover the nearest neighbor algorithm for themselves.
I feel that students can have success with this problem at many different levels. That's what makes me feel good about this problem. There are other problems where younger students are at a disadvantage because they have not learned a particular concept. It seems that a wider variety of students can have success with this type of problem. These are only my opinions.