क्या मारवाडी सच में कंजूस होते हैं?

Three things I hear almost daily. (Mostly people just joke about them, of course.)

1. You're a Marwari... Where is your notebook to note down all the expanses?

Reply: I don't have one. Stop making stupid stereotypical jokes. I carry an expense manager app for that in my phone.

2. It is an expensive place? Wouldn't it be difficult for you to come?

Reply: Yes. But I'll just window shop and then buy the things I liked online getting a 50+50% discount with a credit card that gets me even more discount.

3. Your surname is not maheshwari/jain/agarwal, how are you a Baniya by caste? (Since this would have come into many people's mind by now.)

Reply: Did I ever ask you why despite having intelligent looks you are still so dumb?

Jokes apart, to answer your question, Marwaris are not miserly or shrewd, they're just good at accounts.

And that again, is not a stereotype. It's just that we're brought up in surroundings where people happen to be good at maths. And this isn't bad at all! I, for example, have been giving investment advice to people many years older to me.

People will always crack those jokes on you and ask such questions. It's better you start having fun alongside instead of raging up at every one of those.