Greg-
One of the issues is that the Manx Government [or was it the U.K. in our "best interest"?] signed a "protocol" which in the past served the IOM well. Thus altho' we are not part of the EU [then EEC], we are in the common trading area and for the purposes of free trade must behave as if we were full members.
Thus our law saying that Ice Cream could only contain pure ingredients such as milk, cream, eggs and sugar was illegal as "contrary to free trade" etc