Mopar did this too on their passenger cars in the 60's. The reason for this is when you have loose lug nuts they spin off on the left side with right hand threads and will not spin off with left hand threads, that's why you'll never see left hand threads on the passenger side wheels,
Has something to do with the spinning of the lug nut around its stud while it then spins around in a circle with the wheel. Physics.........
One compounds the spin and the other cancels it out....
But too many people never knew or bothered to look and so alot of studs get busted.
Eric