I think on this occasion it is. We've been teaching leave it and even gone to classes to try to help. We've got to the point when she's amazing at it at home inside but we can't get her to relate it to things on a walk. I can even put a treat on each paw and say leave it and she will. She came top in the class at walking past a lot of different things and not going to them ( I mainly think because she was more interesting in trying to playing with the other dogs though). I'll have a look at the YouTube clip and for a bit I think I'll let her run around to burn of energy for a bit then pop her back on the lead again until I get more control over it. Do dogs not learn what's good to eat and what's not? Thank you for your reply.