Hey TechLord ! Short time no see, you are every where ! hehe
Aaaaah to be Volunteers or not to be… That is the question 
That make sense what you say.
As i know big studio’s works together to achieve incredible games like GTA.
Off course it’s about Money and outsourcing but I like to think they get free deals sometimes by exchanging services each others, i draw you a car you make me a soundtrack.
Volunteers or not, if teams help each other they will climb up for sure