Yes. What you're actually seeing is a player who is not logged into an account. :3 They get assigned your pictogram by mistake -- but other users will see their ow pictograms over these deer's heads instead of yours, so you are still perfectly identifiable.
Every now and then a nameless will take on a different user's pictogram, but it's not horribly common and it's usually pretty easy to tell when it isn't the right person.