Different methods of placing reinforcement in Revit components are shown. 'Expand to Host' is not the only option, you can also use 'By Two Points', 'Free Form' and 'Sketch'. You can also vary the Placement Orientations.
These Revit tools allow you to place different kinds of rebars, like stirrups and longitudinal bars, in a multitude of ways. SOFiSTiK Reinforcement supplies the rebar families for the code dependent rebar shapes.
All native to Revit, meaning that standard Revit functions are fully compatible. Revit constraints for example let you place rebars in a parametric way.