I am not saying caste discrimination doesn't exist. But as an Indian American living in the United States for 20 years, I can tell you that I have never seen/experienced/practiced it here in the US and I will not let anyone do it either on my team (I run a company) or personal family/friends. Having said that, it is a very common joke among a group of Indians when they get together about the whole "vegetarian" vs "non vegetarian" thing. You can argue that it is bad to joke about this topic but it has nothing to do with caste or religion. That's what I am saying.