I agree with both previous comments.
My 2006 Monterey had an "odd" wear pattern on both front tires at 30,000 miles. The outside edge of the right front tire and the inside edge of the left front tire both appeared to be wearing abnormally. The owner of a local truck shop immediately suggested that this could be caused by improper alignment of the rear axle. So, he checked the front alignment and toe-in to assure that all was OK in front and then checked the rear alignment...it was off almost on inch from axle centerline to axle centerline. The rear axle on my coach has adjustable control arms on both sides to allow for proper axle alignment but unfortunately, the threads in the arm on the side which needed to be adjusted had siezed up over the years and there was not enough adjustment remaining in the other side for correct alignment. I ordered a new control arm from Coburg and had it air shipped to me but unfortunately, the mounting bore on the new arm was not the same ID as my old arm so I needed to source a new arm locally. Once installed and with both axles properly aligned, I installed new tires on the front and so far (<6000 miles), my coach handles better and the wear pattern on the front tires appears to be normal.
As mentioned by the OP, rear axle alignment may be as important as front axle alignment to assure proper handling and good tire life of all tires.
Jim