I went to a gold shop in Pattaya to buy gold (obviously). I asked if I could pay with credit card. The lady in shop said "yes" but that I would be charged a commission. I forget what % commission. I know, from my financial services experience, that all merchants , in this case the gold shop, are charged a commission by the credit card company.
I did as previously suggested by another poster. Went to a nearby atm and withdrew cash. Kept the gold in hotel safe.