John McKenzie, it's not really the evil EU that's fluoridating water in the UK. And fluoridation isn't that common in the UK either! Around 10% of the population has fluoridated water: six million people in all, out of the total UK population of 66.5 million people. The Water Act 2003 required water suppliers to comply with requests from local health authorities to fluoridate their water.

Maybe it would be good to speak off the stage, asking festival-goers to ask the people running "this festival and others" to provide tap water rather than making money from selling bottled water that isn't good for our environment?

It was one of the old hippie demands in the 1960s, when soft drinks began to dominate in schools, that all schools and all malls and public places should have free water fountains available. It's a demand that should be renewed.

As for the emptying bottles problem: bring your own flask, and fill it from the bottles, from the moment, and you'll know which is yours. And you'll give a good example to others.