My advice,find yourself someone to pay your bills,while you are practising!!!
i think a son of a friend of my hubby never went to college and makes more than most college grads selling mercedez benz cars. it's just a state of mind, i guess.
For the initial question, no, I don't think it's about aggression. It's a state of mind as well. They just love it and they have the optimal ways of learning stuff ingrained.
You can always be pianist and do somwthing else for a living.She calls it interactive project.She plays ,for instance fur elise and that talks to audience about it!!!!She used to ask them,what they think about author of the piece,music iteselt...etc.etc.People went crazy about it,coz they are part of concerto not just "passive" listeners