I do think that some of the smaller, local makers, might have preferred straight-grained maple, believing that it made for a stronger stock. The prettier they are, the weaker they are. I can think of one maker in my area, Samuel Smith, originally from Pennsylvania, who made only fullstocks. His stocks were nearly always straight-grained maple, with artificial stripe. His workmanship was very good, so I don't think that he was cutting corners. There were other makers in his area, who worked during the same period (about 1850-1870), who often used maple with pronounced natural stripe, so I don't think it was a matter of not having such wood available.