I believe Spoiler is a feature of the Forum to hide information that others might not want to see.
For example, if people are reviewing a book or a movie, they might want to discuss certain aspects, but let others know that if you haven't read/seen it yet, they might not want to read it.
It could also be used to talk about the last five minutes of a Basketball or Football game and you might spill the beans on who won.
You have to remember that the software used for the Ibotta Community is sold to other groups. There may be little use for it in our case, but others might find a use for it.