Animal emotions is a hugely debated and studied topic, at least it was 10 years ago. It was a grave sin to anthropomorphize animals that have not been properly studied when I was in school. That comment is probably a tongue in cheek comment on that
The weird part isn't animals having emotions, it's when they seem to be expressing them in ways that make sense to us. Everyone who's had a dog or cat knows they express emotions very differently from us.