The Gemorah states that the ideal work for a talmid chacham is winemaking. He works very hard two months and the rest of the year studies. The problem is that the wine must be kosher. When the sons of Ahron following in the footsteps of their father and of Moses did not do what they were told concerning the spices (95% of the taste of wine is from it's odor) they had to die. This is a "requirement" because the gematria of the remaining sons names is 1820 like the 1820 times YKVK appears in the Torah etc.. EVEN when we disobey, G-d has it figured out from before.
As a Na Nach you are commanded and expected to do exactly what Saba wants...if he says right is left, so it is.
A non Jew can drink any wine he wants, and it represents no danger to him. A Na Nach is in mortal danger when he makes decisions, and he is EXPECTED to make decisions that go BEYOND what Saba said, just like when Ahron was spoken to by G-d concerning the wine and when he told Moses that he would NOT do as Moses had told him and asked for Moses to re-evaluate his orders.