There is absolutely nothing wrong with using treats to train. It doesn't mean he's not also doing it 'for the love', (which is really the bond you've formed during training) or that you'll need to always have food on you for him to obey you, or that you'll need to use food forever. The idea that a dog will work JUST to please his owner without there being anything else in it for him is a myth. Pleasing you can and should be rewarding for the dog - he gets attention, petting, yummy treats, playtime, whatever floats his boat, so it's not really about pleasing you anyway, it's about learning to get things he values. I don't care how much you love your job, would you keep doing it if you stopped getting a paycheck? If all you got was praise?
Used properly, a food reward, along with a marker such as a clicker or your voice (yes!) tells the dog that he did good. It's a way to communicate to him that what he did is exactly what you asked him to do. Once he understands that (for any given command) you can go to a variable reinforcement schedule, where he's randomly rewarded, or you can reward only the best responses to shape a straighter sit, a tighter heel, or a faster down, etc. Eventually you can phase out the food reward (until you teach a new command, or make an existing command more challenging by adding duration, distance, or distractions), but you can keep up the happy praise that you should be pairing with the reward.
And if he's so distracted by food that he can't concentrate on training you have a perfect opportunity to teach him manners and self control around food! Keefer has always been obessessed with food, and would literally eat until he exploded, given the opportunity. So I taught him that in order to get food he had to look at ME. He could stare at the food all day, but until he made eye contact I would not release it to him. Because he was so motivated to eat, he learned this very fast. There's a great thread on here about teaching focus using food.
At meal time I started making my dogs sit until released to eat. At first I made it very easy, releasing them to eat as soon as I put the bowl down and took my hands off it. If they broke the sit, I picked up the bowl and stood back up. I waited for a sit, and we tried again. Once we had a sit until released at that level, I upped the ante, making them hold the sit until I stood all the way back up, then until I took a step or two away from the bowl, then I moved the bowl closer to the dog and further from me. Over time, I worked up to where I can put them in a down, set the bowl between their front paws, and walk away, even briefly out of sight, and they won't eat until I give the okay. They know the rules and comply because they've learned that's the fastest way to get what they want.
Another training method that might be useful for you is instead of getting frustrated about him sitting or laying down on his own, USE that to teach those commands. It's called capturing behaviors and is as simple as marking and rewarding him for doing what he's going to do anyway. Timing is important, so the second his butt hits the ground in a sit you would say "yes!" (or use a clicker) and give him a treat. The second his but and elbows touch the floor in a down, mark & treat. If you see he's just about to sit or down, add the command right before he does so that he learns to associate the word with the behavior.
You can also use treats to lure him into position, and then mark and reward. If you do use a food lure, get the food out of that hand as soon as possible, using the lure motion as a hand signal and treat with the other hand.
