There are two reasons for that. Reason #1 is because Amex charges local vendors exorbitantly high rates in comparison to either Visa or MasterCard.

Reason # 2 is because whenever a client requests that a charge be removed, Amex pretty much does it immediately and the vendor is basically out of luck.

I recall (not many years ago) when a customer of one of the charter companies I represent claimed he got bad service and wasn't going to pay for his 2-week charter that he had just days before completed.

Amex accommodated him and reversed the charge. It took years to take the customer to court. The company ultimately gave up because the legal fees added up to more than they would have made on the charter, so they wrote it off. That was the end of Amex for many vendors here in the BVI.

Amex does not seem to protect the vendor at all and they really aren't interested in the vendors side of the story. They just leave vendors twisting in the wind.