In all honesty yes Salman Khan is a big name and all but no one has the right to disrespect anyone in a professional setting. The only season I have completely watched was Bigg Boss 13 and he humiliated some of the contestants there. If the contestants take it as a joke then that's fie but if they don't then that's basically bullying which happens all the time in Bigg Boss. The problem is I don't think he even knows what goes on in the house and says what is basically told to him.
Having said that, I don't think he meant "samaan" in a bad way. Even Rubina knows that. From what I understood she has a feeling that someone from the team put that in his mind in regards to the whole her convincing abhinav yada yada. I don't think she's blaming Salman Khan per se. I actually like that she's not afraid to voice her concerns and can stand up for herself without being intimidated by how powerful the opposition is. Also, she wasn't being disrespectful, she didn't use any bad words or didn't yell at him or anything.