Your response to the would-be playwright was financially enlightening, but don’t discourage too much. Anyone who has a real passion for the theatre, the power of observation, research ability and talent to write convincing dialogue should try their hand at writing for the stage. As with novels, the fifth or seventh may be good enough for a try out. There are amateur companies and community theatres happy to mount a well-written local play and provide the first step to Broadway.
But, you’re right, no-one should expect to make a fortune quickly, or indeed ever from it. A friend has just had his second play produced, like the first, at a series of festivals around the country. It is in its third run in this city, at a tiny theatre above a bar which has a reputation for the new and interesting. But, his day job is a newspaper journalist and it will be a long time before he thinks of giving it up, if ever.
Another friend has had I think six plays produced, in several cities. He runs an arts NGO. Yet another has just had his first and only play dismissed as total trash, having ponied up to produce it himself at a college venue, which may have burst his bubble, but at least given him a view of his abilities. It’s a less lonely form of writing and one gets more feedback from table readings than the novelist gets from trial readers. And the prize of success is positively heady.