Most sponsors in egames are looking to provide a product for their marketing.
Most the money these people make are off of streaming and Social Media at this point.
When they make it really big like the Ninja's of the world they start getting into more financial type terms but early on it's more about we give you X product for you to advertise it on your stream,ect.
I believe the last number I saw for Ninja was around a couple million a year.