You spend more because the reticence to buy questionable items is reduced - just put it on the card, the sticker shock only comes once a month.
Until you realize that spending with credit cards is designed to get you to buy more things you will keep spending.
The 1, 2 3% you get back often does not compensate you for the things you buy that you would not buy if you had to pay cash which you may not have in your pocket at the time of purchase.
You either have self control or you don't. Most of my purchases are online anyway, so the cash thing is a moot point. I quit carrying cash over 20 years ago.