If you visit Chanthaburi, I recommended you pay a visit to the Fresh Market in Chanthaburi. Here do have any kind of fruits, vegetable, meat, seafood, and with not expensive price comparing to those Super Market.
The seafood and vegetable in here are fresh and not frozen, they selling off day by day. Most of the people are from all around the city.
Many people in here do not cook food in home, they like to buy finished food with 20-30 baht per pack, and few kind for their dinner.
During mid-night they are doing whole sales seafood, vegetable, fruits, meat, all in here, but during day they are selling normal like this. So here is 24 hours never dark market.