As I recall, if anything in the chain of movement wears it should increase free travel. This would be the cable stretching, the cable housing compressing, pivot points wearing, play increasing in any bushing(pedal, clutch arm pivot), or the throw-out bearing itself. Now wear of the clutch friction disc shouldn't have any effect on the free play, but should have an effect on the engagement point.......I think. That's how I remember it anyway.
Let's see what the real experts say and we'll find out if I passed.