Since this first story has less to do with cons doing anything wrong and more to do with general bad luck, I will go ahead and say that this is basically a mix of my experiences with Ohayocon and Otakon. Ohayocon has given me tables the day of the event because of their at-con table policy, and out of the three times I've tabled at Otakon so far, I've had bags break twice.
Rock on, guys, and never stop drawing.