Every once in a while, there is "that dog," that snoops out meds, and manages to discard them. I had one such. He would fall for it the first time, and then, every time thereafter, was suspicious of such 'treats,' and would either ignore them, or delicately bite them apart to find the pill, and leave it on the floor! He even managed this stunt with a glob of cheese, butter or margarine!
The only way to get a pill into him was the old-fashioned force-the-mouth-open-and-shove-it-down-his-throat method.