I'm with tigger. I use my Visa Rewards card for everything possible. (In fact, I just got to deduct almost a thousand off my credit card bill because of the rewards points I accumulated in 3 years time. They kept having a deal that if you reach a certain number of points you get more points for free, so I kept waiting to cash in.)
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I like the idea of nothing coming directly out of my bank account. I get to look at the bill before deducting the money. And if there is a mistake or fraud, then it is not my problem.
I just had a friend fighting to get money back that her bank had paid to a vendor for a debit transaction. The vendor didn't fulfill his end of the bargain. After a long fight, the bank denied her the money. She got screwed.
Better to have a few weeks delay between the date of the charge to your card and the date of the money leaving your hands. That way if you have a dispute with the vendor you aren't in trouble.
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BTW, I have never ever paid a cent of interest on a credit card.
I mentioned to my mother's friend once that the credit card companies can't be making any money on me. He worked high up in the credit card dept of Chase. He said that all vendors are charged a fee to connect to the credit card network, so all the prices are higher to reflect that. Since they can't generally charge different prices to customers based on their method of paying, EVERYONE is paying a higher price because credit cards exist. (I just hope the markup in prices is less than the rewards the card is giving me. But even if it isn't, it is better to get some of my money back than to get none of it back.)