[Maldo]

I just got a 3 year old male Yorkie. He took to my wife immediately. To me he was aggressive, and bit me ( not seriously ). I knew with time and patience, it would stop. It has.
The only behavior which persists is his behavor with dog treats. If I go to take it he is very aggressive and attacks, this is most understandable. However, he often places them at the entrance of rooms, and then runs to protect them if anyone goes near them, and carries it off to a new location. Often he gets a cookie and then purposefully eats in front of me. He sometimes places them near me and then gets aggressive if I go near them ( ie > while watching tv he places a treat under the coffee table and when I stretch my legs, not knowing the treat is there, he will go for my foot , kind of striking like a snake would it, then take the treat and move it. c
I am just curious as to what this behavior is and why. Sine he was 3 when I got him and he lived in a house with 2 other dogs, I surmise that maybe it has to do with having lived with 2 other dogs. The bahavior was to establish dominance , etc. He also elaborately places his treats around in a line or in a triangle or with his toys. (and of course hides them which I understand). Sometimes he barks at me and I follow him thinking he wants to go outside, instead he goes into another room and then eats a treat in front of me. What is this all about ?? Thanks !!