From my understanding, sponsored bowlers get a portion/most of their travel fees paid for and usually entry fees to the PBA tournaments as a stipend. Still, they are definitely paying some out of their own pocket. Not sure about commercials, appearances, etc.
I posted this elsewhere on the site, but it's an interesting (and slightly depressing, to be honest) read: http://priceonomics.com/the-rise-and...ional-bowling/
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