That's just the point I was making. The nearest example I could think of would be operating a mobile drug testing lab for NSW police. These cost at least half a million dollars, each, and further costs take them to over a million per year, from a bit of googling. These vans only have to identify a few specific illegal drugs and don't require public liability insurance, whereas these mobile drug labs would need to be calibrated to detect adulterants that can be literally anything, test 10 or 100 times faster, and probably would be required to operate diversion programs in order to avoid the perception of encouraging drug use. If I were planning that program, you bet I am putting a shitload of fat into the costings.
This is why I think we are seeing a lot of appeals to the government to step in. If event organisers were wholly or partly responsible, the costs of drug testing to the organiser would drive them out of business.