I am from India, I have multiple cards but most because there is a surge of credit card offers in India, most banks are providing free credit cards and offers to get people signed up.
So many of those cards are just used to utilise those offers to get discounts and a certain select websites for discounts.
But I practically use my debit card, a credit card hooked to online payment services ( paypal et all ) and a backup credit card when I cross the limit of my other credit card. That's all.
One other card I use is just when dining out in which I get some % discount/cash back offers thats all.