In my opinion, it completely depends on the maker.
Higher quality pipes, such as those by Dunhill, tend not to have any colourful bands (with the exception of the spigot).
Mid-range, but incredibly well smoking, Savinelli's do use colourful/metal bands, and (again, in my opinion) this simply adds character to their pipes. In fact, Savinelli's tend to be aesthetically inspired by certain things, such as the Sistina model I just bought: inspired by the Sistine Chapel. Peterson uses metal bands prolifically!
Lower-end (sue me) pipes, such as those by Dr Plumb, tend to follow the route of not adding any decoration, though that could simply be my experience...