The supply of goods or services shall not be granted exemption, as provided for in points (b), (g), (h), (i), (l), (m) and (n) of Article 132(1), in the following cases:
(a) where the supply is not essential to the transactions exempted;
(b) where the basic purpose of the supply is to obtain additional income for the body in question through transactions which are in direct competition with those of commercial enterprises subject to VAT.