It was a festival, not a carnival, and towns/cities often put out contests with prizes under those circumstances. I agree that a carnival wouldn't do it.
Not everything has to be so grand that it's memorable years later. In fact, if you make everything that grand, nothing is that grand. To be memorable, it has to stand out against typical game play, which means you need a lot of game play that won't stand out. The vast majority of ability checks are going to fall into the typical category.
Well, I'm off to Gateway 2019 for a day of convention gaming. I'm sure I'll have lots to reply to when I get back or tomorrow morning.