If the reason understandability is important is that it means you get fewer defects etc, then really it isn't that it's important, it's that defects etc are important. This article is completely confusing means vs ends.
Surprisingly, yes, there's really not a lot of McDonald's or other chain fast food restaurants downtown. You can try exploring in Google maps to get a feel for it (consider eg the area around Mercer and Dexter Ave). You can get to one, but it may be a half hour detour on foot. What is closer will be awkward as they describe.