The RAVE act was passed in 2003 (introduced by Joe Biden funnily enough) and made venues / event organizers liable "for knowingly leasing, renting, using, or profiting from a space where illicit drugs are being stored, manufactured, distributed, or used." with up to a $250,000 fine or "2 times the gross receipts, either known or estimated, that were derived from each violation that is attributable to the person", whichever is greater.

So providing drug testing kits or providing a drug testing station in any official capacity would put the venue / festival officially on the hook for a potentially obscene amount of money because of that pesky darn "knowingly".

Given the current state of the opioid epidemic, I honestly can't understand how this draconian piece of legislation is still law. It is the exact opposite of harm reduction and literally kills people.