The desire to tow with a passenger car is so low that mfg's don't bother with designing a receiver for most models. When they do, it tends to be a very low capacity hitch that's useless for towing, so no need to attach to structural rails. This makes a bit more work for installing a real receiver from a receiver mfg, like drilling through structural rails.
The majority of SUV's and Trucks come from the factory with a receiver installed, so even when one isn't, the mounting points are there, even captured nuts, because it's cheaper to have the guy on the line that installs the nuts to put them into every frame than to check the build sheet.
Another issue is there isn't a lot of room between the bumper and chassis (and bumper and ground) with cars, so the mfg's often have to use tighter turns, tighter tolerances, and additional bracing. $$$
You can get a good idea of the quality of work you'll get from a U-Haul by looking at their vehicles. Except for new trucks, they tend to be in a state of disrepair. I've never been about to roll out with a truck or dolly without having them fix something, and the one long-distance move I did resulted in a blown radiator hose. I've used them in three states, and it's obvious to me that they do zero preventative maintenance. They are a lazy company, with lazy employees that do the minimum they can get by with. There's a reason they are the cheapest receiver installer. You can go to the guy that's installed receivers for 20 years, or the kid that was shown once a few months back.