Inconvenience and denial of a curtesy car

My audi A4 had a funny sound. Reported the matter at Audi service station on thursday the 26th April 2018 and was told it can be booked in for 3 may 2018, that was my first inconvenience. Thursday I was told I will get the car of friday the 4th May of which on the day it was said they've checked and the is nothing wrong with the vehicle. When I drove off the sound was still there, drove back and it was test drived aad the same noise was agreed upon. I indicated from the beginning that the sound is like a worn out CV joint and even this time I requested that they check for it. Ultimately they agreed it's a CV joint and they can only get the part on tuesday the 8th bare in mind it's friday I have plans for the weekend. I requested for a curtesy car which I was told I cannot have it. I raised my concern that I once had a Gulietta and when I has a mechanical problem I was offered a curtesy car for a month by Fiat and why is it not the same with Audi, they just gave me a big NO and the car is still under maintenance plan. Is this a fair treatment?