Unless you already paid for it, you didn't lose anything, so demanding something they can't control is definitely in the ballpark of acting bratty and entitled. There are better way to handle this than "GIVE US NESS OR WE RIOT" spam on every board possible (as the Diretide whining did). There are better ways to handle it, and even if you or I cannot think of one immediately, it doesn't make the only bad decision and good one simply for the sake of being the easiest to come up with.

Yes, they make orders to their manufacturers, but it's not a "make 30,000 asap, please" kind of order. These things are held by contracts and are done months in advance. The likely reason for continued droughts of Amiibo is that these orders/contract agreements on production amounts were made before Amiibo was released, which was a time Nintendo thought they wouldn't sell too well. So until these contracts can be modified or expire and allow for new ones to be made, it may not be as simple as "it's Nintendo's fault AGAIN!", as this honestly could be from their oversight originating from a year ago.

Emails to Nintendo may not give you a response, but be assured, they know how this product has taken off. Sakurai said he couldn't get a Rosalina, poking at the issue. They've also openly stated that they are aware of the scalping situation and are hoping to resolve it in the future. These emails may not give you immediate results, but they do chip away at the right ears due to their shear numbers.

Like I mentioned above, they may have locked in their order count before they knew Amiibo would take off, so their lack of commenting on how they plan on resolving this issue may simply be their uncertainty with how they can work things out with the manufacturers. They can't guarantee the manufacturers are willing to renegotiate favorably, and the fact that these things are done behind closed doors, so just cause we don't get updates, doesn't mean nothing is being done or negotiated for the future.