Many or maybe even most of the place names in Montana are not towns. They are locations that were named by the railroad as stations or spurs that no longer are used or even exist, but have a name on the map left over from railroad history. That is true of many of the place names on that google map of Gregson. There is a town of Anaconda, but Crackerville and Gregson and the rest no longer exist as towns. Ramsay is a small cluster of homes built along the highway, but there are no services. The internet brings up weird info about Crackerville, as it counts the town of Anaconda and others living nearby and give Crackerville a population number as a total of Anaconda and outlying homes.
The Crackerville area is a floodplain that is part of America's largest Superfund Cleanup site, where there is arsenic and heavy metals in the soil washed down from the mining in Butte.