All these rules for what colours should not be put together! It's a good thing that nature never follows anything but it's own rules, otherwise a lot of the flower displays would disappear.....

As has been stated previously, from posters' personal experiences, there are religious groups who seem to avoid bright colours for reasons of their own. This has been the case from the time of the Puritans and Cromwell at least. Maybe these groups feel that it is ungodly to draw attention to themselves in this way or that sober clothing reflects the way in which they think that life should be led. To me it strikes a chord with the Islamic tradition of ultra modest dress. Horses for courses I suppose.