The Grill is an early stage product in Assembly Line 1 to become available. What makes it stand out among other products is just how poor of a product it is.
The Grill is made from a Heater Plate and 4 Raw Iron. Heater Plates have a smaller footprint and have a higher sell price per raw material, as do the Wires the Heater Plates.
The only less profitable way to use ore is to sell it directly without producing anything.