I'm a sr. software engineer and you best believe I spam furry emotes at my coworkers. In my experience and in the companies I've worked at, most people who are even moderately talented operate with a relaxed attitude. As long as they get their deliverables done, don't worry about how they do it. If you've got a problem with them they'll take another offer in a week.

Edit: Also, I'd like to note that I think this behavior is healthy. People should be allowed to be themselves at work. I often joke about people putting on their "corporatesonas" at work.