I understand what you're saying about the teacher taking the choreography coachings alone, but that would not benefit you. I'm sure it can be frustrating just "standing around", but it's important for you to see what's happening and hear the coach's words.
Also, you'd still need to pay the teacher and coach even if you weren't on the lesson with them. The teacher would be learning choreography to teach you. And, rather than using that time with the coach, that teacher could be teaching another student. I don't think it's reasonable to ask for someone's time for free - especially when this is their livelihood.

I am not an instructor, but I have worked in a studio. I know dancing can be an expensive hobby/habit, but I think the price should reflect the quality of the instruction you receive. If it doesn't, then you really need to question your teacher.