For instance, do people prefer the FAI 4km/300 foot finish cylinder over the US 1-2 mile 500-1000 foot finish cylinder? If so, what is it that people find preferable about finishing at 300 feet 2.4 miles from the home airport? Just to do the math for you, that's a 44:1 glide from the finish to zero feet at the airport.

Sure, if your finish point is on the edge of the airfield, which most aren't.