You're being very existentialist, mon vieux, but that's an excellent question. When I think of that and Kmcalpin's query re decisions against us with the Ugly Sisters evening out over the years, I always return to Bob Crampsey's (Brain of Britain and footballing intellectual) retort to those who questioned if there was bias towards the Old Firm.
Remember, he had been watching our game weekly since the 40s. He was quite unequivocal that bias has always existed towards the OF and thought any suggestion to the contrary ridiculous.