If there were a difference we would see it in the video world and don't. One hdmi cable is just like another if they meet the same minimum standards.
I should start by saying that I am a "cable skeptic", but this is an apples and oranges comparison. HDMI is a digital signal that uses differential signaling. This makes the signal quite resilient to all sorts of variations (conductors, local noise, etc.), and any cable will be based on pass/fail criteria. You're either getting the signal or you aren't.
Most audio cables we would be talking about here are passing continuous-time (analog) signals, and any change in the electrical properties can and will change the signal. The cable is essentially adding a resistor between the source and transducer, so the signal might still get through, but it will be distorted.
Now, to protect my "skeptic" cred...it is very, very easy to design a cable where any imperfections (namely, cable resistance) are far below audibility, and any "improvement" would be negligible. The electrical properties of a cable are going to be resistance, capacitance, and inductance, and the materials you use are going to give these values per unit length, making it easy to know the minimum requirements to create a "good" cable.
(tl;dr: yes, there's a lot of voodoo surrounding cable sales, but designer HDMI cables are a special brand of nonsense.)