Price variance between a quart of paint and a gallon of paint are very strange
Here is my take...
Material plus labor = total
Labor to make one qt = labor to make 1 gallon.
Let's assume labor is 100.00
Let's assume 1 qt of material is 100.00
100.00 + 100.00 = 200.00
Volume discount !
75.00 per quart for a gallon of material
100.00 + (4* 75.00) = 400.00