There's no actual assets for the stuff (not that I saw at least). The train cars for both systems are likely static parts of the map, sitting there. There are no active rail lines. Heck, if you follow either the el-train or the rail lines, you'll notice they're broken in parts and worse. I think it was put in to imply the city did have that sort of mass-transit and freight at one point, but by the time the game takes place the city has really fallen. It's a thematic choice to have them broken and abandoned.