Its strange... so there are possibly differing levels of strictness regarding practice shots depending on level of sanctioned/official competition? That does make sense, to be loose with it like that.I would guess that it would be disallowed at most events as a local course condition.
Noteworthy - the rule does still block the specific case of what my friend is doing. Because if he's just missed a putt, he is still in the middle of playing the hole, so the specific kind of practice throw he is taking is still not allowed in traditional golf.