I have, unfortunately, come across the situation where I exchanged one of these tickets for an emote I had already. I assumed that since I saw no text warning me that I DID already own the emote, spent my last ticket purchasing it. It wasn't until I saw that it was grayed out in my inventory that I then realized the error.
I did what I have typically done in other games where I have accidently exchanged an item for an incorrect one and reached out to Sega's support team to ask if there was any way they could help me. Previous experiences in other games games have given me the impression that support typically don't have an issue doing this, so long as there no history of you doing so repeatedly, amounting to you abusing the system.
Unfortunately, they said they could not assist me. I did suggest that they consider adding the same text disclaimer on emotes as they already have on basewear and innerwear to show that you already own the item, and while they did acknowledge my suggestion by reassuring me that they would pass it along, they also stated that there was no way it would be implemented soon.
What really bothers me about this situation is that they provide a disclaimer for items such as innerwear and basewear, since those items are consumed on use, whereas with emotes, which are again, consumed on use, have no such disclaimer. It gives one a false impression that the game will inform you if you already have an item, but should you happen to fall for that false impression, they offer you no recourse.
I made two mistakes. My first, I assumed that since it was a consumable item, that I would receive some notice indicating I already owned it, which was incorrect. My second, I assumed Sega support would be reasonable, and considering the contradictory nature of providing notices for some consumable items, while not for others, realize that the mistake is an honest one to make and rectify it without issue.
If there is one good thing that I could get out of this scenario, it's that my error will be able to prevent others from making the same mistake, and suffering from disappointment.