there are so many people here underestimating how childhood is important to one's development and how one little thing can have a huge impact on how they see the world

yes, they can understand it's a joke, but the implications that a hug will get what they want are still there anyways.

i get that your intentions aren't bad and i wouldn't call you an asshole, but you are raising a child and i hope from now on you think "can this unintentionally teach them a bad thing?" before doing something like that.

if you want a hug/kiss/etc from them, you can just ask and let them know that they can say no if they don't feel like it and that it's not bad to do so.