I am told...how much of it is apocryphal I don't know, but it makes sense...that buckles were often lost. They weren't attached permanently to the shoe. (hence the nursery rhyme) And when they were lost the frugal Scot (or any other reasonable person) would simply cut the "latchets" short, punch a few holes in the ends and voila! lace-ups!

Another observation, as long as there has been a Europe...wars notwithstanding...there has been cross-fertilization in shoe styles. As long as there has been a connection between England and her erstwhile colonies to the west, fashions in shoes kept pace with what was popular in England and in Europe.

For example, throughout much or European history the military and martial events influenced fashions in shoemaking...for both men and women.

The side seam boot didn't really take off in England and Europe until Arthur Wellesley defeated the French at Waterloo. At which point the "Wellington" boot became all the rage and influenced men's footwear in every Western culture for the next two hundred years.

Here in the US, despite a move towards a backeam boot by the US Army in the late 19th/early 20th century, "English riding boots" make up a small percentage of boots sold. The "Wellington"--originally and technically a side seam boot--still reigns supreme.