Quoted from RCA1:How much does the grocery store make on my shopping trip?
Why can't I just buy my food straight from the farmer?
1) Low single digits. Their net profit is razor thin.
2) You often can. But you don't -want- to because you want lots of things from lots of farmers at once. As where with pinball, you're typically buying one game at a time which could easily be done with "the farmer".
Whenever someone asks the OP's question, it's very interesting...and telling...to see people's responses. "No one knows, and you're an idiot...or greedy...for even asking".