I'm not even sure I'd call this a bug. Maybe something unintended, at most, if it even was unintended... During the early part of Kenta's quest for the level 70 mount, when you protect the watch hog, it normally frequently drops pheramones. I just ran it, and it still dropped things, but the event items (N/S/E/W letters and sunshine) were dropping instead, and it was only occasionally dropping pheramones, making the quest just that tiny bit harder. This might actually be intended, but I realized rather quickly this could be abused to just afk farm items if you're level 70 and haven't gotten your mount yet. You can loot up all the event items just before the hog dies, keep those while the pheramones are removed from failing, and then start it over. Overall, dropping the event items just feels unintended. (And no, I didn't try doing it, I just realized it could be done, and so probably was unintended and needed reported.)