I thought that my cat was the only one that loved milk jug rings! When I lived in an apartment building, there was a crack under the door, leading out into the apt. building. I would go to leave and there were always at least 3 on my door step. I am sure that my neighbors thought that I was weird, since I had the rings on the door step. On a few occasions, I would come home, and see a little paw, where Lucy was trying to reach under the door to get her precious toys.