You will find hate everywhere. The US, UK, India and Czech Republics are, broadly, multicultural success stories, but you can find absurd hate, murder, and terrorism in all of those places.
Despite the talk that "coders are masters of the universe", "girls should learn to code", "Mark Cuban wants you to learn machine learning", software development is a labor intensive business (I see managers with a $120k a month payroll wringing their hands over a $9k a month AWS spend) and labor-management conflict as real as it is for coal miners, longshoremen, hotel workers, fast-food workers, etc.
IT workers in many parts of the U.S. have seen operations and jobs go to India. Some Indian companies execute very well, but some do not and then we see the double whammy that IT workers lose their jobs and then system failures have a negative impact on remaining workers, customers, investors, etc.
In terms of call centers, sometimes you talk to an Indian person for customer support and you get great results, but often you don't. Worse, I have received many calls in the last two years from people from India who want to steal my money on the pretense of being the U.S. tax authority or take over my computer and I read that this experience is common. Now many call centers are moving to the Philippines because U.S. citizens can't place the accent.
(Note it is a big labor conflict because displaced coal miners and manufacturing workers and their families could be doing this sort of work. I think of many black people who got into call centers in the south in the 1980s who are great at what they do.)
That said, hate is not good for business. Should you hate your customers, employees, suppliers, partners, community, government? No. There is not profit in that.
If I were you I would contact the supervisors of those people and tell them what happened. That kind of behavior hurts their business directly, probably more than it hurts you.
If I was the supervisor I would probably not fire the people immediately but I would put them on warning, let everyone know this behavior is unacceptable, and if it happened again they would be out.
What they do is up to them, but you should put the ball in their court.