Although Anthracite is the predominant mat color in both the leather and M-B Tex charts, it looks like quite a few interiors include brown mats, so there certainly would be a fair demand for brown mats as well if they were available. Even though blue mats only come in the Medium Blue interiors (123, 205) I seem to see a lot of pagodas with blue interiors (although I've never paid close attention to whether they were medium or dark blue!), so it wouldn't hurt for the Classic Center to produce all three colors.
If the current replacement mats are only offered in Anthracite, perhaps it is because the bean counters felt that they can move more of them in that color and recover their development, testing, material, production and distribution costs quicker. It may also be because it is the same color as the trunk mats already in production so some of those costs can be amortized over more products, reducing the cost per unit. Brown and Blue mats would incur additional development, testing and material costs, so the cost per unit would be higher for than for Anthracite.
Originally there appear to be three holes punched in the driver's side mat posted earlier. The more complexity that is introduced into stocking an item the higher the cost per unit! My guess is that they don't punch the holes in the replacement mats so that there is only one price point and they only need two stock numbers for a set of Anthracite universal mats instead of two price points and four stock numbers for right and left hand drive sets. If they make the mats available in all three colors they would only need six stock numbers for universal mats v.s. twelve if they stocked left and right hand drive sets.
