There is no difference.
Unlike older RGB cables or audio cables which transfer analog signals, the signal is sent digitally with included error parity bits to recover degraded signals (which is the same like you would read a CD).
This means that there is no distortion when there is more noise.
People think expensive cables are better, therefor they rip them off. A 5$ hdmi cable is quality wise the same as a 200$ gold plated one. The only difference is the price.