Food vs Toys in the ring
One of the great things about showing over other dog competition sports, is you can “cheat” and use anything you can (within reason) to get your dogs attention in the ring.
Treats I think are the common choice. Most dogs are food motivated and treats are a quick and calm way of rewarding your dog immediately as well as keeping their attention on you and used as bribery.
Toys are less used in the show ring, but are a keen training tool for non food motivated dogs and a popular training tool for those who have done/do agility/obedience it seems.
Toys can be harder. To show good sportsmanship, you do not want to distract other dogs in the ring. Therefore it is not a good idea to be squeaking squeaky toys, playing a game of tug or playing ‘catch’. However, the use of a toy as a lure is fine. Sometimes, a dog just knowing you have something they want can change the way they work for you, so feel free to take in a small toy that will fit in your pocket and then let your dog have a game after the class, away from the rings.
Remember when in the ring to consider your fellow exhibitors and show good sportsmanship at all times.