The trouble is pretty much everyone also wants at least some extra spin on a ball you have to pay for. I would imagine the market for a slow meter ball with no other attributes is pretty small, you may well be the only customer.
While the balls we use here obviously don't cost WGT anything to produce, they do have to be added to the game data base and pro shop during a down time, therefor the cost isn't actually zero.
And if there are unlikely to be many people interested in the product then I would think it's unlikely they will ever offer it.
On the other hand they did add that ridiculous slow meter starter ball for 100 credits a sleeve. Zero spin or distance, 1 durability and 1 meter. I should imagine they must have sold at least, ooooh, none of those.