This dog has been conditioned to eat a treat when it is presented to him by a person who positions their hand and holds their hand in a certain way. And they eat this treat even when it isn’t there, when it is entirely fake and just thin air. And it appears that this dog is enjoying the treat because he licks his lips afterwards.
Two useful tags. Click either to see the articles: Speciesism - 'them and us' | Cruelty - always shameful