My baby? Or my puppy?

We are having a real problem (well, I don't know that it's an actual problem...it's just weird) with Barrett lately: he keeps pretending he's a dog. I have no problem with him running around on all fours with our dogs, but he's taken it even further. Because our dogs tend to beg (and Barrett tends to give in) while we're eating, we put them outside during meals. When the meal is over, we let the dogs back in and they charge for the table, hoping that Barrett dropped something and he usually has. Well, Barrett has started getting down on all fours and pretending to scavenge with them. Sometimes he even eats the stuff he's thrown on the floor. Yuck! I've also caught him attempting to eat dog food out of the dog bowls several times this week. Twice he's come up to me with a sort of disgusted look on his face and I've held my hand in front of his mouth to catch the dog kibble that he wants to spit out. Ewww! He's sneaky about the dog water, too. He'll lie on the floor and take big swigs of it before I can even think about catching him. Ugh! I usually hear water splashing and then tell him that boys drink out of cups and not out of bowls on the floor. The other funny thing he does to pretend he's a dog is that he barks whenever Max comes home. Our dogs run to the door and bark whenever he gets home from work and Barrett just joins in. He gets on all fours and yipes at the door just like a dog. Max has learned to open the door very slowly. I'm sure this is all normal toddler behavior and I'm totally fine with it, but I could do without the gross parts! I'll have to try to get some pictures of him being a dog.