Until and unless you’re caught in a massive shitstorm in life, you should be able to pay for your basic necessities with your monthly salary. Using your cards for purposes like buying groceries and paying off utility bills is often the first step of losing control of your spending. You don’t wish to make the Rs 100 you spent buying vegetables cost you Rs 1000 with interest, do you? Not using your card will also help in keeping your expenses under control. Keep your cards for a purchase that you perhaps don’t wish to make with the money you have. Like buying electronics or getting flight and hotel tickets.