I don't agree. It's subjective but it's paid. Also, it's not always that the buyer decides the price of labour. Most of the times, it's the seller who decides. But generally it's decided by reaching an agreement. 

IamSINGLE

The problem is we don't know how to value human labour. If I'm a truck driver delivering water to a remote location, how much should I be paid per hour?
Value is subjective and only the buyer can decide how much I should be paid. If they decide the truck driver's labour is only worth $10 per hour, there may be no truck driver willing to deliver it.

SpaceHodler

science

Tap water is safer for drinking than bottled water, says new research

I agree but only for the human labour that's involved in bringing water to remote places. I still don't want that water should be sold. 

My point is that it should be clearly mentioned as a message on water carrying things that "water is free" but you pay for human labour and logistics 