Sometimes this argumentation is totally valid. For example, it's utterly stupid reasoning when one uses less water at home "to save fresh water and environment", because households use half of the fresh water used by industry, and agriculture uses twice as much as the two combined. Whatever inconvenience the person trying to save the environment this way puts themselves into, the effect is capped at about 10% of total fresh water consumption. It's an effort applied in the wrong place.
More philosophically speaking, if there's an equation of life with all the variables and we apply it here by taking all the "saved effort thanks to not promoting water consciousness in regular households" and dumping it into whichever area we'd think is ideally efficient, it wouldn't be _too_ surprising if holistically, the result comes out less favorable of this approach vs just telling regular folks to save water. For example, consider that it might take tenfold the effort to convince an agricultural company CEO to change approach; if ninefold the effort doesn't reach the activation energy to convince such person then you're better off telling nine people to stop the waste.
In general, I have the feeling that many decisions can wrongly be made to look stupid if we recalculate it using the select few variables we care about.
Ah yes, "let's show them not to be wasteful". Ever heard of the activities of making industries not to use child labour or improve working conditions of factory workers? If they didn't work, why do you think this one would?
> Where would the change be coming from?
Certainly not from social movements. They rarely have enough power to make a single company change, much less a whole industry.