I'm really surprised at how many people dressed up for this event seeing that it is quite limited in theme (japanese, ninja, festival, kimono, fox, raccoon are keywords for most avatars I'm seeing today).
It isn't really the type of event I would typically dress up for but I had a new Fille (horribly hard to match even the texture of it) that I wanted to try and I thought it would fit the theme well. I only had the old Fox ears/tail and was not going to invest in new ones that would be overpriced and gather dust after the event.
The items I already had hanging around my inventory. One thing I hate about dressing up for events is how expensive the items that fit the theme or match the freebies become. This is why I usually don't dress up for Christmas.
Halloween is much more free, you can pretty much do any costume type theme for Halloween