Every year, I am afraid to say, seems to harbour at least one student who thinks that he or she can get around the Wizarding Examinations Authority's rules. I can only hope that it is nobody in Gryffindor.
After packages are driven the last mile, Digit carries them the last 10 feet and they say it can get around objects though it may have to step on the grass to do it.
The last mile is the problem and half the world now lives in dense cities and people spend, depending who they are, between 90 and 95 percent of their energy getting around on foot.