Hose bib below grade, yard hydrants
You'd probably need a double check valve like a sprinkler system to put a garden hose connection underground.  

For the yard hydrant:
Your link says "Frost Proof" which is different than "Freeze resistant".  Further your referenced code says " that incorporate a stop and waste feature that drains into the ground".  The description for the yard hydrant you have linked says "Unlike conventional hydrants which drain the water into the ground, these use a reservoir below the frost line to contain the water".

I'd argue that either point makes this portion of the code inapplicable but certainly the 2nd portion where it doesn't drain into the ground at all.