On character development
In the comments to this film, I see a number of people talking about how there is little to no character development, and that it leads to a piss-poor film. I wonder if they watched the same movie I did. Perhaps it is because there were not many (if any) scenes where a character walks out onto stage and proclaims a grand turmoil and how it has affected their life for the richer. Absent any exposition, I can see how people can miss out on the internal conflicts, but they are certainly there, plastered over the actors' faces.
Take Chris for example: he strives for exceptionalism, to prove that he is different from the other personal trainers out there, but is humbled by rejection. Sure, he's great at what he does, but in this economy nobody can take a risk on him proving out. [Keep that in mind.]
Meanwhile, he dates an escort who specializes in the Girlfriend Experience, offering herself as an emotional companion as well as a sex object. Already there is the baseline: how can he tell his experience with her is any different or more genuine than Chelsea's paying clientele? Rather than focus on that insecurity, he sublimates onto her personology books. This forms a schism in their relationship when Chelsea is willing to take a risk on a client to see if his exceptionalism proofs out based on the personology he dismissed so he wouldn't have to think about how genuine/disingenuous their relationship may be.
By the time he's in Vegas, he has no idea where his life is going. On the flight, one of his companions mentions the incredulity of trying to find love in Las Vegas (Sin City). It's a ridiculous concept: trying to find an emotional connection in a city devoted to vice and carnival, an escort city. Add to that the conversation about the plausibility of being in an open relationship, and Chris's subsequent thousand-yard-stares as he hits on the Vegas girls, and it's safe to assume there is a character arc in there.
(And that's just looking at the side character.)
*****
When I am king you will be first against the wall.