What modern institutions did Costermongers fill in the 1800's London and what are some of the merchandise they sold? What did the more intelligent costers do?

Costermongers or street vendors filled the place of today's coffee shops, convenience stores and fast food restaurants. They sold many items, but most commonly nuts, oranges, apples, flowers, needles, matches, greens, snacks and meals, herring, violets, watercress, pins and thread. The most intelligent and well-to-do costers sold food and drink, including baked potatoes, fried fish, meat pies, eel pies, cakes and tarts, coffee, tea and ginger beer, berries, ham sandwiches, milk, elder wine and peppermint water.