Well, if you've been stop start driving in traffic or going down a long hill you'd expect them to be able to burn your hands, yes. If they're binding when you've not got your foot on the pedal that may be a problem. Rear pistons can rust themselves into the slave cylinders , so it might be valuable to slip the pads out and see if they can be pressed in and out freely, perhaps with a brake expander or a lever of some kind. They're usually a bit stiff but if they're in good condition it should be possible to move them.