Margarine  was originally manufactured to fatten  turkeys.  When it killed the turkeys, the people who had put all the money into the research wanted a payback so they put their  heads together to figure out what to do with this product to get  their money back.

It was a white substance with no food appeal  so they added the yellow colouring and sold it to people to use in place of butter.  How do you like it?   They have come out  with some clever new flavourings.