OR you could make friends with some cat owners and offer to clean out their litter boxes! Why would you go for artificial cat poop when the reason thing is available? Your dogs would love you even more.:)
My dogs prefer rabbit poop and they can find in right in our back yard.
My late JRT loved the litterbox snackbar. The fact that she had to dig for her treats was an enjoyable bonus.
[I did not endorse this behavior, but I also couldn’t do a whole lot about it.]