One more update from Andy, the owner of Gelato Mio:

Via our email exchanges, he’s told me he’s very grateful for the forgiveness he’s seen from many atheists. I told him not to let the ones holding grudges get to him.
Three of the people behind Skepticon (Organizers Kayley Olson and Micah Weiss are in the picture below) have also forgiven him and they left a message saying as much on Reddit (***Edit***: The post says that JT made threats against Andy. I’ve read JT’s posting on this subject and that’s absolutely not true):

We’d be real appreciative if anyone who put up negative reviews without ever having gone to Gelato Mio would take them down. I mean, Skepticon, as a conference, hearts local businesses. We want to support our community as much as possible and make them see how awesome atheists and skeptics can be. So, in general, that means not running local businesses into the ground. 😛
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tldr: Andy is a pretty nice guy who made a mistake. Skepticon likes him. You should too.