Cannot spin rear tires by hand?

hey guys
the rear of my gfs 05 tiburon is making a weird clunking noise i thought it was the struts
I removed the rear wheels to have a closer look, i noticed i cannot spin the driver rear tire freely ( ebrake is off and car is in neutral ) and the pass rear wheel is hard to spin
I looked at the inside pad on the d side ( wheel that wont spin freely ) and the pad is pretty low and a bit oily.
other side is the same but not oily.
if the inside brake pads are low could this cause a clicking/cracking noise in the rear?

also shouldnt the rear wheel be able to spin freely?

Chris

Edit: Removed driver rear brake and the wheel will now turn by hand. Would this cause a cracking noise when going over bumps in the rear?