I had an interesting chat with one of the traders at Download, he told me he paid 15k for a pitch, that is three days plus maybe the Thursday night and Monday morning. He told me also that all food and drink prices are fixed by the management, even showing me a sheet of the set prices to charge! Maybe op should look into doing less commercialised events like smaller festivals and bike club rallies etc. Smuggling stock in and selling it 'under the radar' in the campsites at big events has it's own risks if you get caught. They have plain clothes security as well as badged.