Sometimes it seems that the factory guys just do what they like and expect the industry to adapt to it. It took so long for the manufacturers to admit that people tow things with their trucks that everything was pretty well sorted by the time they got into it. One would think they would look at what other's had done and not only mesh with it but exceed what the standard was. It doesn't always work that way though.Most likely if its one of the newer hitches, then the hooks did not fit and he just said screw it. I need to change the hooks on both the camper and utility trailer so they fit, or put in shackles to hook the chains to. Automotive engineers did not think that one all the way through. should have put 2 anchor points on there for chains or made them fit the standard hooks that come on campers and other trailers.
If GM wanted to take the lead they could equip all of their trucks with a 2 5/16" ball and RV style socket on the back and an industry standard cross member under the bed that could accept a goose neck ball or 5th wheel hitch. Then all of the 1 7/8" and 2" hitch balls, flat pigtails and other weird towing stuff would go away.
I have no idea why we have the two smaller hitch balls. They don't cost significantly less and they are just plain less capable. I can see how the flat connectors came about but it is time to retire them. I have converted everything I own to the 7 blade RV connector but I still have to carry around adapters to make everyone else's wiring work. It's time to rationalize the system.