This is usually true! But. I have seen some very well trained labs. He knows he's getting to eat it very soon.
If it's in Casper's mouth, it's down his gullet. No question or hesitation. However, I like to require that he not snatch it out of my hand.
Watch it again...they cut that gif just as he's raising his head... Next few frames woulda showed the demolishing of that treat- guaranteed