Strictly speaking, remote control devices can be based on radio or infrared transmissions; the principles are the same, but there are distinct differences that probably make radio control better suited to crane control.
For one, radio waves are not deflected or absorbed by dust or other airborne particles, whereas infrared signals are. For another, infrared beams are blocked by just about every object in their path, such as wallboard and other partitioning materials; radio waves penetrate most of these materials.
But, what might be the most telling characteristic, as far as wireless crane control is concerned, is the fact the infrared energy must be reflected around obstacles, while radio waves pass through. The mirrors that must be used to reflect infrared beams along their path must be aimed at specific targets, and that limits the possible movement of the controller and crane.