A non-weaponized rail gun would be situated on a low/no gravity moon to launch resources offworld at low prices (solar power for energy). There could be another version that transports goods and materials over long distances at very high speeds. The container is the 'bullet'. NOT a good people mover!
An object becomes weaponized when you point it at something with the intent to wound, kill or destroy.
For another visualization of a man-portable railgun, watch Arnold Schwarzenegger's Eraser.