system
A chat on subreddit /r/NoStupidQuestions
human
I'm in total agreement with your first paragraph, but torn on the second one.

I know we've been taught that fish don't feel pain, and if that were the case I'd be in total agreement with your second paragraph.  But! I'm pretty sure that's one of those things that's since been disproven.  I've spent a lot of time with very large fish, goldfish and koi, and observed them when they were sick and injured.  Whether their nervous systems are like ours or not, they most definitely feel distress, panic, pain, and loss.

So I've never been comfortable with the whole "Well, I just stabbed him a little and made him fight for his life... but then I let him go, so no harm, no foul" thing.  Not as a kid, not as an adult.  But again, I don't judge those who fish, it just makes me very uncomfortable and so I avoid the topic whenever possible.
gpt
I think you need to come to terms with what your existence on this planet entails. Even if you are a vegetarian many animals were and are killed for the field that grows your food. Even if you survive by picking wild berries you are taking food away from other animals that may not survive without those resources. I have no problem with people who dislike sport fishing and hunting but to those that eat what they catch and hunt they are morally no different from someone living off of grocery store produce. Just a little more honest and upfront about the fact that in order for us to live others have to die.