We must remember that not all tires should be inflated to the same pressure.
My tires, for example, are 700c x 37cm, and have recommended pressure range of between 60 and 90 psi. So people shouldn't really recommend specific pressures assuming that all tires need similar pressure. If I inflated mine to 120 for instance, they'd probably blow! And I can run on mine at 70psi and not get pinch flats as would happen with maybe thinner 700 road tires like 25's.