Right so I stumbled onto something similar while looking into Mothman territory around here in Point Pleasant - there are a load of old B&O Railroad routes running through this area and when I started mapping reported Dogman encounters against them the overlap is honestly kind of unsettling. Not a perfect correlation but enough to make you go hmm.
My theory, and its a loose one, is that the old rail corridors basically created these long undisturbed strips of woodland that run for miles and miles. Perfect travel routes for something that doesn't want to be seen. Whether thats a cryptid, a misidentified known animal, or something weirder I genuinely dont know.
What areas are you seeing this pattern in? I'd be really interested to know if its happening in the Pacific Northwest too because the rail network there is massive. Someone with better GIS skills than me could probably do something proper with this data.