I usually find eating at community profit, food stalls, for example, the CWA, Scouts, Church groups will give a reasonable quality, safe food handling, burger, better than the chips, Pluto pups, jam donuts available from many food vans, though I think these mostly appeal to the teenagers, not the grey-nomad who wants value for their money.
Things to watch out for to avoid a bout of gastro after the show is that any food that is not cooked in front of you is kept at temperatures below 5oC or above 60oC up until serving time. Food stalls must provide protection of the food from contamination from flies, dust, dirt, direct sun, human breath or smoke. Food stalls must consist of a roof and three sides enclosed. All stalls to be situated on a readily cleanable surface, e.g., concrete, brick paving, duckboards, tarpaulins or heavy duty plastic. And the floor covering to extend beneath server tables.
The worst ever example of food handling I have seen was a chicken van who cooked the chicken at the back of the van it served from, out in the open and the stench of the thawed defrosted chicken before it’s being cooked was overwhelming. These days I even sniff around the back of a stall before I buy from the front and I only order chicken or fish if I feel I know and trust the food stall operators to be as food safety conscious, as I am myself. I got a nasty bout of food poisoning from a dish of garlic prawns bought at the Royal Melbourne Show. I buy a chicken and mushroom dish from an Asian food stall I know; you can watch it being cooked, he puts the chicken frozen solid into the wok, cooks it in front of you, if I am there early when it is first being prepared, there is no possibility of contamination.
If in doubt, look for the obvious safe food handling techniques and do not buy food being cooked by the same person handling the money or stored outside of a bain-marie once cooked.
If you are at a show in Western Australia, I can recommend, Western Australian lamb, ‘The Lamb Van’ for a great just like home cooked, lamb shank. J Yum!
As for drinks, it is almost a fashion accessory these days to carry your own, bottle of water as you walk around a show and to have backup water containers to refill from, in your car.