HI Lluis,
Customers are allowed to have a SAP system without the Support of SAP AG. Every customer can contract the support with a third-party supplier to get the technical support. This also applies to others SW like Oracle, JD Edwuards .....
Of course you still have to pay the license of use for the SW but not the Support part.
This is the case that I have raised in this Blog. The point is not the way you access to the SAP support but who gives actually the support.
Kind Regards