Agreed. If you got thin spacers, and the studs stuck through, you'd only be able to use them if you had a wheel that you could drill relief holes into the back of the mounting surface.
For instance, this wheel comes cast with such relief cavities:
There are thin, thin items we call shims (and the manufacturers often call spacers) that don't have their own studs, and rely on the OEM stud to continue on to the wheel, but those might get you 3/16" or 1/4" movement and that's hardly ever enough for decently upsized offroad tires. They're usually just for ricers. (hint: We mock ricers...

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