Because none of the other choices stand a chance.
At Star Wars Celebration a couple weeks back, Hasbro shocked us all by announcing that the widely popular and highly collectible Vintage Collection would be returning after a few years of fans screaming at them to bring it back. It was a joyous occasion, and one that will be long remembered. They also announced that the first figure to be released on the vintage Kenner-inspired card would be chosen in a fan poll, and that is when the trouble started.
There is a contingent of Star Wars fans that has decided that since Lucasfilm decided to move all of the pre-EU (Expanded Universe) content under a Legends banner to make way for new cannon stories in the era of Star Wars, every chance they get they will "stick it to Disney" and make sure that old EU characters and stories win every poll. They even go onto the Amazon pages of New Cannon books and novels and down vote and give one-star ratings to try and tank sales, in an ill-attempt to bring back the old cannon they liked. It's all quite silly, but people, especially Star Wars fans, take themselves way too seriously. So when the fan-poll started, they organized and all voted for EU character Ben Skywalker, Legends son of Mara Jade Skywalker and Luke Skywalker. This pissed a lot of people helping run the fan-poll for Hasbro, and also served to shoot themselves in the foot.
The top six figures receiving votes for each collecting site were tabulated, and in the end, it seems Hasbro left out the Ben Skywalker votes entirely and came up with the following six finalists: Emperor Palpatine (Return of the Jedi), Ahsoka Tano (Rebels), Yak Face, Doctor Aphra, Sim Aloo (or Imperial Dignitary if you are a vintage Kenner collector), and ARC Trooper Fives (Clone Wars). One of these will be the first 3.75 inch super-articulated figure when the line returns next year. Unless a miracle happens, I can pretty much say with certainty then Aphra or Ahsoka will win, and collectors will whine about it, and while they do have a point when they say that both these characters already stood a good chance to be made, it is neither characters fault that they are extremely popular. And for the people with no agenda, who maybe did just want to see a Ben Skywalker made, they are screwed. Once again: fandom divides, names are called, and feelings are hurt.
You can vote in the Fan Poll for the next Vintage Collection Figure now through May 2, with the winner announced on May The Forth next week.