Last time I checked (lie: I never have) people have always been happy with the colour of ketchup. Tomatoes are red. Ketchup, made from tomatoes, is also red. Move on. Heinz, the people who should really know about these things, decided that it would be necessary to bring out green, purple, blue and 'mystery' coloured ketchup turning a popular sauce into a terrifying experiment. Children and the colour-blind were nonplussed. The rest of humanity wept.
Read about these and more, and be glad these things are not on your menu today. Link -Thanks, Ben!