Interestingly, I have a second set of "regular" Raschigs as pictured in the Dufferin brochure, where the cue ball has a small circle on it. My other set doesn't have a cue ball with a circle. I remember asking the Dufferin rep if the Centennial style Raschig balls was a copyright violation. He said that Raschig is in West Germany, and they can do whatever they want!
However, I have seen a set of Brunswick Centennial balls where the the numbers, including the circles and darts, were in the stripes! They were apparently made in very small amounts by Hyatt of Albany, NY and the owner said they may have been called "Royal" Centennials. Of course, when Hyatt went out of business, Brunswick got Aramith to start making Centennials. But as I understand, it took Aramith a while to achieve Brunswick's specs. I don't think Aramith has ever made any Royal Centennials.
Raschig also made a 9 ball set without any numbers. I think they did this because, as accurate as Raschigs are, not having any numbers made them even more accurate. It's probably mentioned in their 9 ball brochure, but I can't read it because it's in German! Attached is a photo of my Raschig 9 ball set and the brochure.