A little bit of a rant

So I was watching this episode of HIMYM in which Marshall, who works for an environmental law firm, is in a case against a pharmaceutical company that has started to pollute an important lake. If he wins, they'll have to pay a fine and stop their activities regarding the toxic spills, and if he loses they'll carry on polluting it.
And throughout the episode, he has foresights of what the future of the lake will be based on how the trial is going. In these, he envisions himself talking to a teenage Marvin (his in-the-chapter newborn) while they fish in the lake, sitting on a jetty. And it's this scene that bothers me.
Marshall's professional goal has always been to "save the environment", to "protect the earth" and all that, which I find noble and praiseworthy.
In the bad future, there are no fish and basically the lake is covered with small flames. There's even a monster, a mutation or whatever. So the reality here is clear. The lake is no more a sanctuary of life: it's toxic and dangerous. And then there's the other situation, the good one.
Here the lake is peaceful and seemingly full of life and they are... Fishing. This I find particularly ironic (and sneaky). Sure, they saved the lake and now the fish are alive and healthy... But they're fishing, this is, they're killing them for their own egotistical purposes. They don't respect (not to consider love) their lives: for future Marshall and Marvin, they're just things, not living beings.
So I'm beginning to think maybe Marshall's motives aren't so laudable, so good in the end. He doesn't love the environment, he doesn't care about the fish themselves. He only likes the lifestyle that he can afford in a world that isn't ruined, a lifestyle that is still based on believing other species are inferior and therefore he can dispose of their lives. In short, he's a bit of a hypocrite. In the end it's only about himself, sadly.
Of course, this is not the only occasion in which this irony is displayed, but this is one I felt particularly vexed about, and that's it.