It doesn't come up often, but anatomical differences in the Quackers Universe can sometimes be a source of contention.
I often find that no matter the scope and scale of the cartoon universe you see, little thought is paid to how the characters ended up the way they did in the broader scale of things. Not so with Quackers! Indeed, much thought has gone into how the animals of this world - not to mention their human counterparts - have evolved, adapted, and otherwise managed to cope in their day-to-day lives. Some fair better than others, but ultimately most get by OK, despite the occassional hiccup. A lack of thumbs, or even a full set of digits, isn't the setback that it once was. (You know, I have way too much time to think about these things...)