> In what situation were you as a foreign traveler where you needed to pay UPI?

All the time? Credit cards are only accepted by fancy places and cash is increasingly a hassle, especially in a tech-forward place like BLR.

The final straw was when I bought some biryani at a shopping mall food court and tried to pay cash. They had no change, the neighboring stalls had no change, and this wasn't some plot to extract money from the gora, they genuinely didn't have and couldn't find small bills.

In the end they tried to wave it off and discount my meal by 40 rupees or something, and I rounded up by 60 instead. And I remember thinking I probably just created another problem, because now they need to balance the books and parcel out the cash tip without change.