You actually use it! ;>) - Parking brake cables rarely get lubed and tend to get rust and gummed up inside the sheathing. If your adjusters are working properly they shouldn't need much unless you brakes are not holding well enough...which isn't the case here. (Like the grandmother who never backs up her car!! --which is how they work BTW) Most likey your cable isn't retracting enough due to low spring pressure or just need to get lubed or replaced. They can be a real bear to free up. try shooting a bunch of WD-40 in the sheating and actuating the cable a number if times, have a buddy with a pair for vice grips grab the outer ends and pull it back and forth while you hold the the release lever and move the cable in/out. If that doesn't work, I'd consider removing/cleaning, or get new ones.
To get the shoes to move back in, you need to hold the adjuster lever away while you back off the star wheel a few turns....easier with the drums off. Might as well clean them up while your that far in there....new brake shoes too?...