I don't think a single trainer will argue with you that they don't use conditioning. Yes. They train animals. Yes, they use food as a form of reinforecment. But they also use other forms of reinforcement. Such as Jello, Ice, rubdowns, toys. I've even seen an entire show done competely without food as a reinforcer.
Animals at Seaworld are never punished. They never have their food withheld from them. I've seen several "training sessions" that aren't really training sessions. Where all they do is feed. Not a single behavior is asked for, no training, or "learning" is happening. All the animals do is eat. But you don't see thoes sessions in shows, because all people want to see are the big fun "tricks".
So what happens if an animal doesn't do what the trainer wants? Yes, you're correct. They get a "LRS" or Least Reinforcing Siutaiton. Where they just don't do anything for 3 seconds. And then move on to something else. If the animal doesn't want to cooperate. They can't make them. They just get their food at a later time in the day, it doesn't mean they don't get fed at all.