If your pup or dog snaps or takes a piece of your finger when offered a treat it can become a real problem and accelerate quite quickly. This is not what you want especially if your dog plays with children.
Now if your pup is snappy it can be that it is so food motivated that it wants it all now and is unaware that its teeth hurt you. It can also be caused by young ones being a little hesitant when the dog comes for the treat that they will drop it just as the dog goes to take it. What does the pup do? Snatches it as quickly as possible, sometimes before it hits the floor. Therefore creating the snappy behavior.
There is a relatively easy fix for this. It should be started only by adults then you can supervise and teach the kids how to have the dog take treats gently.
We will generally start with something of high value that is soft. A hot dog slice the thickness of a quarter or a small piece of cheese.
What you need to do is hold the treat between your fingers and thumb so the pup can smell it but can not get any quite yet. Now here is where you must be brave and might get a little scratch on your finger or thumb from their needle sharp teeth. Ready?
Allow the pup to smell what is concealed between your fingers and thumb, be prepared and act quickly. If the pup makes contact with your fingers with its teeth you must swiftly use the back of your hand and give a light tap on the nose and say OUCH! Then offer again. If contact with teeth accrues again repeat. After a few tries the pup will start to lick at the tip of your fingers. Hooray! Now as he is licking you will slowly squeeze the tasty stuff so he is able to lick it from its concealed place. Any teeth remove your hand and try again after a few seconds.
You can move on to biscuits by concealing them in your hand letting them sniff them out and gently opening your hand and let them work them out nicely. If the pup is too assertive you remove your hand and try again. He will quickly learn that by being gentle gets him the treat.
Then teach the kids how to offer biscuits in the same fashion under your supervision. In no time the pup should be gentle in taking a treat.
Often this can be resolved in a day or two if you practice it a number of times.