There's no such thing as lbs/ft of energy
Energy and torque are dimensionally equivalent (force x distance) however they are obviously different concepts. Torque is basically a rotational force, so to find the energy produced by a given torque, it is multiplied by the angular distance traveled, measured in radians, which is a dimensionless number, hence the dimensional equivalence. To distinguish torque from energy it is written as lb-force-feet, or joules/radian