I tell my dogs "good" and that lets them know that what they just did or are doing is on track, but I don't consider that payment. They like praise and that is always a good thing, but when learning a new behavior, I pay them with whatever it might be that they want at the time or in the context. Its like if your boss praises you and tells you what a wonderful job you did, it feels good and its nice. But its not a pay check. That is what really makes you get up in the morning and go to work. I enjoy paying my dogs with what they love best. And affection.....they get that anyhow quite a bit, so its all good, but its not just out of this world like praise and a treat. Thats even better.
For example: If my dog wants nothing better than to go outside and he's at the door all excited, opening the door is reward enough for sitting nicely and waiting first before busting out. LOL. He's probably not interested in getting a pat or even a treat would be secondary to getting that door opened.
If the dogs want to get into the car to go for a ride, they must wait first, then letting them get into the car is their reward. They love getting into the car. Same with getting out to go on a special walk or hike somewhere else. They must wait when I open the back of my car without being told until I give the "ok" and jumping out and rip roaring up some hiking trail is reward enough for having wated nicely until released.
If Lyric wants to chase a squirrel and wants nothing else, a "good boy" isn't going to cut it for payment for coming and sitting instead of chasing the squirrel. So, payment for coming and sitting first, for me is to let him chase the squirrel afterward. I don't worry about squirrels in this woodsy area. He'll never get one. But he sure loves the chase and it's an outlet for his prey drive. Teaching him come in spite of deer and other animals consisted of more involved training than that but that's the idea behind it. It involved a structured setting up of the dog's environment and setting him up so he couldn't fail.
For a lot of obedience skills, I use a variety of reinforcers, depending on the task and what might interest him the most at the time. Treats are good for a lot of things and a rope toy works for some things. For new behaviors or more difficult ones, it might be a higher value reinforcer and for already learned behaviors, a lower value treat might suffice, but its good to mix them up.
Behaviors which take a lot of concentration and are of some duration, I usually use treats because the dog can eat the treat quickly and get on with it, where as a toy would disrupt the task. For instance with heeling. In the beginning, its important to reinforce very, very frequently to show the dog that the position he is in is correct and a very worthwhile position to be in. Later, as he gets onto it, I'll spread them out a little more and so on. If I stopped to let him tug on his rope toy, he'd loose the continuity of the heeling. So, I don't like to break up behaviors of duration with toys and prefer treats. They're quick. You don't have to take them away again and most dogs love them. But they can lose value if they're always the same, so depending on the situation, I might use a piece of kibble and in another situation I will use a piece of steak or chicken.
I might use a toy for payment for an already learned, good example of a long down/stay with me out of sight but I usually use a treat and a game....both for something like that. And at the end of practice time....lots of play and affection.
I don't always have treats with me when we go for a hike and that's primarily when I do most of the practice. Sometimes I take them in my pocket and sometimes I don't. At those times, I just praise and play. But I won't try teaching something new with nothing in my pockets. I really want to reinforce those unlearned things to get them going.
So, reinforcers vary hugely for me. There's more to it than that, but that's long enough. LOL.