[Sangetsu]

In small town festivals, it is usually locals who sell goods and such, and in order to get permission to set up your own place, you are going to need to become buddies with the festival organizers. The spots aren't expensive, there just aren't that many of them.

In larger festivals it is more of a problem as many of the vendors are associated with the yakuza. Junior yaks get their start in the gangs by running food stalls and cheap games (older yaks are into prostitution, porn, loan-sharking, and gambling). If your food stall is doing more business than the yak next door to you... you get the idea.

When I lived in Chiba, there were two large festivals each year, the hanami festival by the lake, and the summer festival in the downtown area. Most of the vendors in both festivals were yakuza. I wouldn't want to try open a booth at either festival.