Unless you are selling via an actual marketplace such as Amazon or eBay, you are not compliant unless you use your own IOSS number. Logistics or other companies in the delivery chain are not, by definition, facilitating sales as the regulation presumes. 

The purposeful misinterpretation has been overlooked by EU – for now. As it is explicitly prohibited in the regulation, the practice will be targeted by tax administrations. 

The reason why it is expressly prohibited is that it creates a number of problems with utilising the wrong party IOSS numbers. From the customs point of view, the data becomes both unreliable and opaque for their purposes. Once the actual seller is behind an obscure, unrelated party, it becomes difficult or nearly impossible to know the seller, the actual origin of the goods or the actual party with product liability.