My sweet older dog will do just about anything for a treat! I showed this java bean treat-toy to her while I stuffed appropriately sized treats into it, then held it up for her to sniff. She showed a little interest in it for a minute, but when the treats weren't immediately popping out for her, she ignored it, and hasn't touched it since.
Could just be my particular dog, who hasn't been the super-curious treat-and-trash snuffler that some dogs are? But for our household, it was not effective.