Do I really need rear brakes?

Hi folks,
I have now got around to pulling off my rear drum to have a lookey at the 
rear brakes.  The situation was that I failed for braking differential 
between the front and the rear brakes in the state inspection.  The 
assumption was that the rear brakes were worn out at 90K miles.  I had
done 
the fronts some time ago.  I was expecting to have to bring the drums down

to the shop to have them cut while I swap out the shoe parts.  To my 
surprise, it all actually looks to me to still be OK, with a lot of pad 
left.

I posted a few pictures (the first time I have done that - yep I am so 
proud...my daughter helped me there - links below) that I would like you
to 
please look at and either confirm that I do not need new brakes or set me 
straight in whatever way I need it.

When I took off the drum, before I messed with the star adjuster, it
seemed 
kind of loose to my uncalibrated feel.  The drum was loose enough to
rattle 
in my hand on the studs, it just would not come of due to the ridges in
the 
drum.  When I was adjusting the shoes to be able to get the drum off, I 
first moved it a bit in the wrong direction and it tightened up so the
drum 
did not move.  It seemed like there was a bit of adjusting done to get
that 
far.  It is all dry in there - no leaks.

So here is what I am thinking now.  All I need to do is put it back
together 
and adjust to wheel stoppage and then back off a bit so it moves with just
a 
little resistance.  Then try running it through inspection (which is free)

again.  Cool?

I am wondering at this point why they would need to be adjusted.  Do they 
not self adjust when I back out of the garage every day?  Is this
something 
I need to do periodically?  What is up with this?

Thanks folks for your insight.
Tomes
(also posted to other NGs)

The picture links:
Entire assembly.
http://i203.photobucket.com/albums/aa190/BrennaToman/CIMG1001.jpg
Top of rear shoe
http://i203.photobucket.com/albums/aa190/BrennaToman/CIMG1002.jpg
Top of front shoe
http://i203.photobucket.com/albums/aa190/BrennaToman/CIMG0999.jpg
Drum - no gouges at all on surface that is meeting up with the pads
http://i203.photobucket.com/albums/aa190/BrennaToman/CIMG1000.jpg