Even the kids watching this would scratch their heads in befuddlement...Eat the food (which is already dead) but don't drown it, kids! Honestly who lobbied for this ad and what was their ultimate goal?

This was played then the HUGE condiment lobby went to Washington and put a stop to it!

ranch dressing will destroy the south

This isn't as silly as you think. An important precursor for the synthesis of the explosive RDX is found in mayonnaise. During the cold war the government was stockpiling RDX based plastic explosives, so to keep their costs down they needed to reduce the demand for mayonnaise. Of course, they couldn't come right out and say this (or the communists would start doing the same, sparking yet another arms race), so they slyly discouraged consumption of mayonnaise through these PSAs. The more you know.

There was another PSA with that "Time for Tymer" guy that basically said the same thing with "Don't Drown your food". Does anyone else remember that?

Heh, I have to eat drowned food!