There are places that have thrown public money at freight choo choos in efforts to replace some truck traffic and reduce train idling & other emissions. Often, small railroads can get public money to upgrade weight capacity on key lines to 286K# - if no bridges are involved, that can be relatively cost-effective compared to upgrading a bunch of roads to handle larger/heavier trucks. For the most part (ignoring projects like the Colton and Stockton crossing grade separations), those are fairly small projects even in raw numbers, let alone compared with what road reconstruction for bigger/heavier trucks costs.