Artists can also often work in isolation, especially someone already regarded as a genius. I suspect plenty of people have a tendency towards eccentric behavior, but suppress it because they need to participate in society in order to survive. A genius engineer for example is less able to be wildly eccentric, because an engineer is inherently dependent on others and depends on others to implement their designs.

Another example is the stereotypical eccentric mathematical genius, of which there are endless examples. Pure math shares something with art here, in that a single gifted person can produce important results independently. I mean, I'm having a hard time coming up with very many examples of famous mathematicians who weren't a bit strange.