Serious Brake wear question on 2008 Caravan

I have a 2008 Dodge Grand Caravan, SXT, with the 4.0 liter, 6 speed.
This model came with the 17" wheel standard. 90% of the time only one
person, the rest of the time 2 persons are transported.
Brake wear seems to be out of control compared to previously owned
1997 Caravan ES, 3.8.

At 11989 Front pads were 8+mm
At 14710 Front pads were 2 mm
Rear pads were 6+mm
Front brakes were replaced.
At 14770 Front pads were 7mm
Rear pads were 6mm
At 18842 Front pads were 7mm
Rear pads were 2mm

Does this look normal for the wear?
I was under the impression that the front brakes did something like
70% of the braking. On my last Caravan, I was getting like 50K on the
rears. The 18842 figures were provided by the (5 Star) Dodge
Dealer's "World Class Inspection" when I took it in for 18K service
(oil/filter/rotate tires). The other numbers came from previous "world
class inspection reports from the same dealer's service department.
It just seems that the brakes are going much faster than they should.
I am NOT a left foot braker. On long downgrades, I downshift the
transmission into 4th or whatever is needed to maintain appropriate
speed, and only touching the brake once in a while. I follow good
driving practices, no excessive speed, slowing by taking my foot off
the gas when I see slow traffic ahead, or a light getting ready to
change.
I have NEVER discovered that I was driving with the parking brake
engaged.
Could I possibly have a rear parking brake that's not totally
releasing?
Could there be a F/R balance valve that's not doing it's job?
Any other suggestions?
This is getting expensive at $300 an axle for brakes.