Simply put, AmEx is not taken as readily as Visa and Mastercard primarily because it charges a processing fee higher than its competitors. So, not unexpectedly, at some bars on St. John, you might as well have left the card home, for all the good it will do you at closing time.
“For my business, AmEx charges double what Visa/Mastercard/Discover/Diner's charge”, said St. John Julie, a jewelry store owner at Wharfside, in a comment on TripAdvisor.com. “Credit card companies fees are based on volume,” she said. “Since 99% of the businesses on St. John are small and independent, we don't have enough volume to get good rates.”
However, another self-identified island retailer said he likes to see that green card. “AMEX customers seem to have higher disposable incomes and spend more $$$$; making them well worth the extra percentage we have to pay.”
AmEx gift cards are also usable many places. StJohnMax said Woodys, Lime Inn, and Cruz Bay Prime “gladly accepted” his cards.