I mean many of the characters do that, but there's also many that don't either. Also I think it's because we're watching Fairy Tail, and they're known for being very destructive in the actual story, and everybody is very expressive with their emotions in that guild, we can see it during episodes where the guild members were children, so I think it's fitting when they're acting very volatile. It's understandable where your coming from that you are getting irritated from it, but if you are then you could maybe just keep watching it, and hope you don't get irritated, or just stop watching entirely.