You are mistaking biological utility for economic value.
And even then, water and tuna have very little utility to a biological system that already has plenty of both. The utility of adding more may even be negative.
Eh, no worries. You gave good advice, and it sounds like it was heeded. You left me confused, but no big deal - I've been confused a few times before...
no, water and tuna have measurable and objective value to your biological system.