[armydoc]

I use my Amex creditcard for EVERYTHING.

I suspect not everything, because there are still a substantial number of merchants that don't take Amex. So, it is wise to have a fall-back Visa or MC rewards card for those. Like you, I buy everything by CC, pay the bill in full, and reap the rewards.

[Vaquero]

you’re right....there is a minor percentage of merchants, though not substantial around here in NY. Most major internet sales takes it also.