A lot of people have complained that the Canto Bight scene has a rather juvenile animal cruelty message. I agree that this is not the place for such a childish and basic message, but I'd like to point out just how nonsensical this whole sequence is aside from that.
1. They make no attempt whatsoever to free the slave boy.
2. Freeing one animal (and causing property damage out of spite) is worth failing your mission and dooming the Resistance?
3. There's no indication that all of the people (or even most of them) in the casino are responsible for selling weapons and ruining Rose's home. The whole "these people got rich selling weapons" thing is the pure definition of generalizing.
4. I doubt everyone in the casino was a rich person, there weren't any slaves or paid servants/butlers in the building at all? They could have injured perfectly innocent people.
4. There's nothing inherently evil about what's going on in the casino, even if they all are weapons dealers.
5. Guess who's going to be cleaning up the mess Finn and Rose made? It's not going to be the rich people, it's going to be the slaves.
6. The only person we see abusing the slave boy isn't a rich person, it appears to be a hired hand. No revenge is taken against the one person seen directly doing something evil.
I could also go into the fact that Disney, Lucasfilm, and probably Rian Johnson himself are insanely rich, but that's been mentioned before.
This is so nonsensical and lazy that it boggles my mind thinking how it was even approved for release in a major motion picture, much less a Star Wars movie that everyone will see. I'd be embarrassed to put a situation like this in a movie. It's obvious that Rian Johnson wanted a "heck yeah, fight the power" image in his movie against "evil rich people", but put zero thought into it beyond that. There are plenty of ways to do this basic thing. Guardians of the Galaxy Vol. 2 had a completely justified "fight the power" scene. The Last Jedi handles it in the most juvenile and lazy way possible.
With this kind of thing in the movie I really can't understand why so many people think Rian Johnson is a good storyteller.