I know a country the size of Missouri is way easier to wire, but that is no excuse.
Actually its half the size of Missouri.
Well, Scotland has 5.2 million people in 30,420 square miles and Missouri has 6 million in 69,709 square miles. For those who may be mathmatically challenged, that's over twice the area with only 20% more population. So, when you consider the supply and demand model, there just isn't enough money in it to make it worth while (yet) to have highspeed connections everywhere yet.
The flip side to that is every moderately metropolitan area in the U.S. has had highspeed connectivity for years while Scotland has only just acheived that same coverage, when you factor for population density.