The occupation of someone who sells plaice, cod, mackerel, and shrimps is typically a fishmonger. Fishmongers specialize in selling a variety of seafood, often working in markets, fish shops, or grocery stores. They may also provide advice on preparation and cooking methods for the seafood they sell.
The Hatter
A grocer, or greengrocer.
News vendor .
a confectioner
That would be a milliner.
someone who sells goods someone who sells goods Supply and Demand.
a butcher is an occupation that sells and slaughters animals to eat.
The Mad Hatter is a hatter. He makes and sells hats for a living.
In the words "painter" and "seller," the suffix "-er" indicates that the person is performing the action or function associated with the root word. In this case, a "painter" is someone who paints, and a "seller" is someone who sells.
A person who sells limestone,
Someone who does, or sells drugs.
It's an old term, probably obsolete by now, but someone who sells fabric is called a mercer.