I see more than a few bikes with worn out clutches at under 30k miles and as low as 18k miles. If they're used for commuting in heavy traffic and the rider feathers the clutch or rides the clutch the majority of time it'll wear out. It's a single plate dry clutch, Just use it as a switch to change gear and not to adjust speed/progress in heavy traffic.
And as you've said before, if people had seen the size of the release bearing, they wouldn't sit at lights in gear with the clutch in.