By Bryan Smith on January 10, 2015 at 11:00am
The reason why there is such a small supply of Rosalina & Luma amiibos could be because of people who buy the figures in bulk and possibly sell them for a larger amount of money than the original sale price. The term for this is "scalping," and while it's mostly used in the context of concert or sporting event tickets, this unsavory practice can still be used to apply here. One person, in particular, is buying a lot of certain amiibos and then reselling them for a large amount.
The person taking responsibility, mariotehplumber (who ironically has a YouTube page full of nothing but "Sonic the Hedgehog" content), was recently been interviewed by Nintendo Nuggets (the interview is no longer available to view). He says that he is buying the amiibos in bulk because he "hates Rosalina's fans" and the character herself.
There is also his YouTube page, which shows pictures of him giving the middle finger above a box full of the rare amiibos, such as Marth, Villager, Wii Fit Trainer, Little Mac, Captain Falcon, and Pit. Please view the video in the link at your own risk, as it contains a lot of obscene language.
Mariotehplumber has also stated that he will be hunting the Lucina, Palutena, Robin, and Zero Suit Samus amiibos, whenever they are announced, with his reportedly "$35,000 funds." It's not specifically clear where he is getting these funds, whether it's from selling the rare amiibos for large amounts of money or from another source (such as job, family, etc.).
For those who are collecting amiibos, it would be a wise decision to start pre-ordering certain figures before the supply is gone.