Richard is such a fat cat businessman. He owns several supermarkets.
The expression is primarily used to describe a man (usually not a woman) who, although rich, is not seen as industrious. He has perhaps become wealthy through hard work but is now relaxing, or he has never had to work for his wealth.
17. Fishy looking or sounding suspicious
They won’t say where they got their computer. Their story sounds fishy to me. I think they may have stolen it.
Someone called on the telephone telling me I had just won a free trip to Hawaii, but first I had to buy his or her product. It sounded pretty fishy, so I hung up.