@Nunya Bidness
This is what you were looking for for the farmer's marker question. If you wanna relay to the person who asked. 
It went widespread when Square (Block's POS) started accepting Bitcoin, but it is a separate group. They do have materials about Square for merchants though.
Bitcoin Merchant Community
Bitcoin Merchant Community
The Bitcoin Merchant Community is a growing global community of small businesses helping one another defeat 3% credit card fees by accepting bitcoin
