Question: The bobblehead feature which shakes user avatars only does so when scrolling *down* the page. When scrolling up, the avatars do not bobble. I paid good unicoins for this!

Answer: 
This is not a physical question, but a legal one.

As commentators in the Arnold Schwarzenegger Bobblehead Doll War have noted1 (emph. added),

> 
> The **very act of creating** a bobblehead doll out of an individual's likeness **sufficiently distorts** the likeness beyond a mere literal depiction to create the intended **comic** effect characteristic of bobblehead dolls.
> 
> 
> 

According to this legal scholar, the actual movement is irrelevant. The *making* of a bobblehead alone is funny in and of itself. Please laugh now.

In addition, the article argues that a bobblehead is an, albeit untraditional, medium of expression that is protected under the First Amendment to the US Constitution. And that is just lawyer-speak for "When it comes to bobbleheads, we can do whatever we please."

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1William T. Gallagher, *Strategic Intellectual Property Litigation, the Right of Publicity, and the Attenuation of Free Speech: Lessons from the Schwarzenegger Bobblehead Doll War (and Peace)*, Santa Clara Law Review, Vol. 45, 2005, Page 595
*This answer may be recorded for quality control purposes*

Consider asking this question on [Physics Stack Exchange](https://meta.stackoverflow.com/posts/227403/edit), which discusses bobblehead-physics related issues rather than unicorns.

Though to be a good sport, I will give you a link-only answer to the [Second Law of Thermodynamics](https://en.wikipedia.org/wiki/Second_law_of_thermodynamics) and [Perpetual Motion](https://en.wikipedia.org/wiki/Perpetual_motion) which it states is impossible as a result.