I only have about ten hours in a J-3, though much of that solo. My instructor said, "be careful not to groundloop…" just as he, uh, groundlooped taxing back after landing.
People are lazy with the rudder unless they have a reason not to be. We teach coordinated flying - aileron and rudder together - so why would you need the rudder on the ground when the wings are level? The reality is that each control has the ability to make the aircraft do what we want.
One of the best lessons I ever had was when a German aerobatic judge said I could use whatever control(s) I needed for the results I wanted. Sometimes rudder makes the nose go up, sometimes you push the stick to make the nose go up. All depends. I've not flown a taildragger since taking up aerobatics, but I think I'd be more confident.