Just because you trim the ribs it does not mean that the bits you cut off are wasted. The part with all the cartilage in my opinion is not pleasant to take a bite out of so it is much better removed. Some on here do like it though and leave it on.
After you have removed the membrane, by bending the ribs find the point where the bones meet the cartilage and cut along the join using a sharp knife.
Retain the meat that you have cut off and continue to cook these off-cuts in the same way as you cook the main ribs.
When the ribs and off-cuts have all finished smoking - while the meat is still hot, on the off-cuts pull the meat away from the cartilage for use later. If you wait until the meat goes cold it will be more difficult to remove. This can then be cut into cubes and used in other dishes - like BBQ beans