Noticed this one during the latest Cebakul suicide party:
When trading tickets for wine of the dead, if you click on a stack of tickets you get the usual "All 5 | 4... etc" popup, but it only trades one at a time, regardless of your choice. And it trades the first one in you inventory even if you clicked on any other ticket you have.
(BTW, love the idea of this item/feature and the fact that it stacks at 13 items :) )