Not quite as fun, but if you go to the
Disney Store and search Aulani, you will find several of the items that they have in the store there. I've noticed that they switch out what is available at the Disney Store from Aulani quite a bit, but right now they do have the beach towel that we got at Aulani last summer on line (they have 2 online- we have the one with the characters on it). The towel has a bad review, but I don't agree with it. We love our towel- and it is no thinner or different that any other towel we have gotten in the Disney parks over the years (and we have several). In fact, I see several things that we bought at Aulani available on the Disney Store website right now.
Aulani has a ton of Duffy merchandise. There are a large number of Japanese tourists that visit the resort and Duffy is huge in Tokoyo Disney, so they definitely cater to those preferences. In fact, when we were at Aulani, of all the characters, Duffy always had the longest line. My DD adores Duffy, so she went nuts at Aulani. There are Duffy and Shellie Mae, shirts, ornaments, suitcases, Pins, clothes, plush, mugs, cups, postcards, and on and on and on.
The robe they have at the Disney Store now is the same one they had in the rooms at Aulani and sell in the store there. We have one of those at home too--- and in addition to the people size, Duffy has one his size as well!