I'd say it's not galaxy-wide, but it's also not localized. In other words, if you want to see it because you think it'd be interesting, then see it. If you don't think it'd be interesting, don't see it. It's a delicate balance between keeping the Fairy Path the galaxy's most mythical "secret" and having enough interaction to RP with people.

After all, the whole point of hyperspace is that it has handy tunnels through realspace that can act as shortcuts. So it seems reasonable that you'd get the glow in other parts of the galaxy nowhere near Finnegan's.