Our costumed turnout was low, but we had a ton of kids end up participating. I can't go into detail without outing myself, but I definitely dressed up, and it was a hit.
Overall, it was fun, but it would have been better had there been any real advertisement. Target made one event thing on Facebook, and a few coupon slips printed a few weeks ago, but that's it. There should have been signs and flyers.
I liked it, though. Only sucky part was having to go from working the event to the sales floor for another 4 hours while in costume. I have no shame with stuff like that, but some of the comments were disconcerting....and far too sexual.