I don't think 90% of people have done this. In fact, I'd say I've seen someone lowering through chains less than 20% of my time at the crags, and TRing through them even less than that. I've only been with one climbing partner who has actually done this.
This is a site where new climbers (myself included) come to for information. I believe in the courtesy of leaving the outdoors in the same condition you found it, including small wear on chains. In the interest of preventing excessive wear (and subsequent replacement) of rap stations, people should be discouraged from lowering or rapping through chains.
And besides, if you're going to be lazy at the crags, what does that say about you when you get out into the mountains?
