The credit card companies normally charges the merchants 3-5% over the transaction cost.
If I use a credit card which gives me cash-back, and I pay off the card balance every month, why should I use cash instead?
Exactly!
I feel like I'm giving away money if I don't get the rewards from my card. I lose nothing using them because I pay them off every month, and I get back a 1-2% on everything because I charge it all.