I understand the trainer's point that if Riley always gets super yummy stuff then he won't be as motivated by treats, but I think for most dogs there is usually something that they absolutely love that is a great reward for them, whether it is liver treats (my dog's favourite) or pieces of cheese, or praise, or a particular toy. My dog gets table scraps (healthy ones) regularly, but he still goes nuts for liver treats, cheese and eggs especially. I wouldn't change his feeding schedule, but just find what his favourite rewards are that motivate him the most.
I've read before about using a