At a glance, these look like modified C clamps or U bolts.
The problem I foresee is added friction on the ball, causing wear and tear.
If the concern is the nut backing off, why not just tack weld it?
As for security, I don't see how these are any more theft-proof
than a padlock in the locking mechanism.
Add 37 cents to this opinion and you will have enough to buy a postage stamp.