Disney's animation team likes to have fun by making subtle references to other movies, characters, or real-life Disney employees in their movies. For example, pictured above is a screenshot from Frozen. There's a tiny Mickey Mouse figurine in Oaken's trading post. You can see it clearly at the 0:37 mark in this clip.
This is one of 22 Easter eggs that Brian Gilando of BuzzFeed found in Disney movies, both recent films and classics. You can find the rest here.