VENDORS HAVE NOTHING TO DO WITH MUSIC
Leave them out entirely! Bring your own food....post the phone number of the best delivery pizza place on a phone pole or tree. Give people the directions to the nearest cut rate liquour store. Tell them the name of the hotel with the best toilets in the lobby....

Hospitality for performers is ok if you can get them away from it!
Generally performers cluster in roped off private hospitality zones networking with each other while of course neglecting the most important purpose of the day- REACHING the Public. If performers want to network fine....schedule a time to do this before or after the event.
A good way to do this is to have coffee, bagels etc in a meet and greet session before the event. While orienting performers give them an hour or few to talk and network.
Same at the end of the festival while collecting feedback give the performers time to network and unwind.

I believe that hospitality is extremely important. Most grocery stores will give you at least one grant per year. Hit the bagel and pizza places....beg beg beg and you will be sure to have great results just keep at it. Never offer money before begging.
Dont leave out the beer places. Micro breweries can easily kick in a keg of beer. I have had great success with them. But if you offer money before begging they will have to take it and you loose it.

I have never really seen a successful way to feed performers but accomidate public too. I really hate the difference that the barrier makes. Perhaps my most memorable experience was sitting down with a Czech performer of folk songs at a smithsonian festival in DC. They had given him tickets for beer etc....which he did not have to use himself. This way providing hospitality to a performer makes it also accessable to an ordinary peasant member of the public who wants to sit around with him and learn music or a technique or two...

I would probably go for that method.
Provide tickets for free food-perhaps even at the performers tent.
Then allow the performer to give half to a non performer or several.

When festivals only last for a few days out of the year it is essential to use the most possible time to spread the music. This is not done to a large crowd via stage. It is done feet in the dust sitting around sharing and playing.

Conrad