I think Ronnie's lumping all wealthy people into the same group is based on his personal experiences. I would imagine that he feels inferior/insecure in some ways due to being looked down upon as he was growing up for being from Bangladesh- -and even now that he has more opportunity in the United States, his livelihood depends very much on fooling people about where he came from. He fears at any moment that everything he has worked for could be taken from him. And I know that when I feel insecure or frightened by someone else's perceived power over me, I sometimes "protect" myself by falling into the generalization trap.
I do not think all wealthy people are the same everywhere. By saying they are, Ronnie is doing exactly what he dislikes about the Bengalis. An experience with one wealthy person, or a group from one region in the world is not representative of everyone who falls into this category. I think that Satya, after spending two weeks on the road with wealthy Pival, would also disagree with him too.
The more connections we make with people who are different than we are, the greater chance we have to see them as individuals rather than through the lenses of our biases and stereotypes.