ME: "Hi I need a gallon of Williams Emerald Urethane Trim Enamel in 7006 'Extra White'"
Employee #1: "Oh.. I think that the base color is 'Extra White'
Employee #2: "No, i think the 'Hi-Hide' base color is 'Extra White', the base color 'Ultra White' is different now"
Employee #1: "Are you sure? I thought all the base colors were the same."
Employee #2: "No.. you are thinking Laytex. Urethane is different"
Employee #1: "So if he needs 'Extra White' he should get 'Hi-Hide' or 'Ultra White'?
Employee #2: "Bob.. grab a can of 'Ultra White' and we'll do a comparison with a swatch of 'Extra White'"
another employee joins.. [we are now 15 minutes into my time at the counter]
Employee #3: "I've got the swatch.. open each can"
Employee #1: "Its close.. but 'Hi-Hide' white looks more white than 'Ultra White'
Employee #2: "Yea.. 'Extra White' and 'Hi-Hide' seem to be the same..
Employee #1: "That will be $110 please!"

One of the levels of hell is the Sherwin Williams 'white' section.