The places where I can't use my American Express have been almost non-existent. One or two mom and pop restaurants were Visa only, but that is about it.
Almost all of my monthly spending is on my American Express.
Almost all of my monthly spending is on my American Express.
However, you have to setup the American Express account separately, which probably has a lot to do with why many mom and pop type restaurants don't take it. But now that a lot of new restaurants seem to be using processors like Square, this is a complete non-issue.
I shop at farmers markets quite a bit, and a lot of the merchants there are using Square, and it is awesome =)