That's a lot better than the 15% rate on Ecodiesels.
A friend of mine delivers trailers, up to 30,000 lbs. worth at a time (stacked), for a manufacturer. He drives enough to buy a new Ram every four or five years. That's normally at just shy of 500,000 miles.
He has yet to have to replace any brake components before trade-in time. I tow less weight, but never bobtail like he does on the return trips, and at 23,000 miles there's no measurable wear on my pads.
Yours probably does need new pads, but not because of wear.