I think it was more of a case of what paint was around after the war. I remember my old man painted the whole house in green & cream gloss as this was what he got from London transport at the time ( read pinched probably). There was not much colour choice around then so you will find most makers who used an external source would have similar colours on their toys.
Nice mixers Steve are they both red & green or are they more orangey colour - I still have to find the red body, green barrel version, plus a few more colour variants on this model.