This could be perhaps the difference between a supermarket and a wet market. The stallholders know their regular customers and would exchange greeting followed by perhaps some updates of the economic situations - perhaps preparing the customers for price increase (^^), and recommending what's the latest in the vegetable scene. From mainly Cantonese in the old days, we see a bigger variety of Chinese dialects and the inevitable Mandarin these days (with younger Singaporeans and mainland Chinese) and English with the Singaporeans who are more comfortable with English and the domestic help (commonly known in Singapore as maids) - Indonesia and Filipino forming the bigger groups. In Chinatown, there are some Singapore Indians doing the marketing and so, there's some Malay being used (the common language in the old days).
There are also the business customers, mainly from the food stalls in the Food Centre on the 2nd storey in this Chinatown complex. From what I observed, there are also the chefs from some restaurants who came to pick what's the freshest for the day. Big restaurants might order directly from the wholesalers in Pasir Panjang wholesale market.
Customer loyalty could be seen when we saw some stalls with many customers while other "pa mun" (beat mosquitoes as they say in Hokkien) - meaning idling and hence looking for the unfortunate mosquitoes, but it would be a tough exercise these days in Singapore. Some customers are repeat customers over more than a decade. Despite the change of location after the last renovation, they came flocking back once they could locate them. Some of them would even asked about the stallholder's children, tracking them since the time when they were born. They even know which stallholder has married a wife from Indonesia or mainland China!
In some stalls, there are already two generations working together. The older ones might recommend how to treat the vegetables and how they should be cooked. No, no takeaway recipes, just some aga-her and aga-there (approximates as is typical of Asian cooking).
I hope to post pictures of the vegetables and might need your help in identification, especially in how each is called in various languages, in various Chinese dialects and other languages, be it English (English and American!), Malay, Tamil, Hindi or even Tagalog, or Javanese.
What vegetable is this?