Drugs at Folk Week

Local story: potentially fatal drugs that were stolen from a tent at the Broadstairs Folk Week campsite at Upton School grounds in the town have not been recovered. Police issued a warning after three 50ml bottles and three 30ml bottles of heroin substitute methadone were taken between midnight and 6am the following day.

So, what was such a drug doing at a campsite during Folk Week?

Presumably, someone trying to get off heroin addition? I don't know what the dosage would be for methadone, but the quantities seem to be rather a lot.

But, it was for a whole week, I suppose.