The problem they face with colors is that all the cars built at the Oshawa plant (Camaro, Impala, LaCrosse) have to share the plant's color palette, which is 12 colors.
All cars built there are painted in the same paint shop. Having different paint shops for each car would get stupid expensive.
Now you're thinking - ok 12 colors, how come Camaro only has 10?
Well the other 2 colors are on Impalas & LaCrosses that would look stupid on Camaro lol - beige and brown I think. There's also 2 colors used on Camaro that are not on Impala & LaCrosse... Inferno Orange and Rally Yellow. If I guessed correctly, the other 8 colors will be used on all 3 cars.