There is a common misunderstanding about using rewards to train dogs. Yes, some trainers use food to lure the dog into a specific position. I am one of those trainers. Luring is only one aspect of it though.
Using food to get a dog into position can help a dog understand what your asking them to do and many dogs will easily work for food. Once the dog learns what they need to do to get the food, they usually will repeat the behavior over and over again. At this point you can add in a verbal cue
( command ) Since dogs learn through association, they figure it out. First they associate the behavior with the food, then the word with the behavior and the food. Did you know most dogs can learn over 200 words?!
Some dogs, however, aren't interested in food at all or are too shy or stressed to accept food from a human hand. These dogs need something else to motivate them. When I say motivate, I mean excite them. I feel it necessary to clarify this as I have seen other trainers " motivate" dogs by rough handling using force or tugging a choke chain. This is really unacceptable and unnecessary when you could just get the dog to perform a behavior in exchange for a small piece of meat, the toss of a toy or a short game of tug.
Using a motivator, inspires the dog to perform a behavior and makes them enjoy and want to do whatever it takes to earn the reward. If you are using food, you can always fade away the use of a treat, but you can never take back rough handling or abusive actions.

So...in short the message here is THINK POSITIVE!