Speakers work more efficiently when hung, lights wouldn’t light very well if they could only be set on the floor, and you couldn’t see a video screen very well if it wasn’t suspended in some way. In the production world, hanging things–whether from existing structure (the building) or by building additional structure–is called rigging, and we do it all the time. While procedures exist for making sure the resulting product is safe, that doesn’t mean everyone follows those procedures, or is even aware that there is a procedure.