From my understanding and memory, the show we see Jupe perform was the first one. He was feeding the alien at the exact same time of day anytime he brought out a horse as he explains to the audience. Earlier in the film, when OJ heard Jupes’ speech from a distance, it was at night, so clearly not the same time as the show later in the film was more around dusk which means this was Jupe simply rehearsing his speech and not the actual event (plus, why would have the event at night, the alien would be far harder to see). It’s also why the alien devours them all, all the prior feedings only had Jupe present so presumably a (shaky) bond was formed, but the moment a bunch of other eyes were looking at it, it was all over.
As for profit, you have to look at it psychologically from Jupe’s perspective. The Gordy event would be clearly traumatizing for a child, and we see moments of him struggling with the memory of it. The Gordy museum he made is basically his way of forcing himself to confront those horrific thoughts head on, like a person with arachnophobia filling their home with posters of spiders, little plastic spiders, etc. He sees this alien as a way to conquer this mental issue fully. The people who ran the Gordy show failed to safely utilize a potentially dangerous animal in their show, but in Jupe’s mind he will succeed. He WILL perform a show with a live audience (just like Gordy’s show had a live audience) and it will be a success. He is so determined that this has to work he was even willing to have his wife and children involved despite knowing the risk.
And of course, we know how it all ends. It‘s why as much as I love OJ, Em, and Angel, it was Jupe’s story I loved the most, a person who survived a traumatic event but took the wrong steps in addressing that trauma.