lol I agree, that was something that always bothered me about this episode. I would've just called it a treasure or something, but I guess they wanted the alliteration.
It's funny how differently we see this episode. Nearly every point you take off for the episode is one that I either liked or was at least neutral on. Like you found Sandy's song to be the worst, but I lowkey thought it was the best. Though one thing I hadn't thought about which you pointed out is that this episode really relies on everyone only having one real interest. And I suppose on one hand it's fair because this is a special with a lot of characters and so giving them too much complexity could muddle things, but also it is a slight disservice to their characters. I think that at least SpongeBob had more depth in this episode than it might seem, but yeah everyone else was kinda just relegated to one big interest (I don't think they were all relegated to one character trait, though. Like Sandy, for example, had her interest in science but also in karate in there, and we saw that she is protective of her friends in her song).