I listen to every new thing I give to Blathers, especially if it's bugs. He gets so freaked out that his fear of bugs get in the way of explaining them in a comedic way. But on a serious note, I listen to Blathers' facts because I get to learn a snippet about that bug/fish/sea creature. I even screenshot them all in case I forget.
I listen to everything because I love zoology in general, even though some of the facts are already known to me. I’m disappointed by most of the butterfly facts because it’s always how gross their caterpillars are. I wouldn’t mind it if there were caterpillars in game (which I really with they add actually) but I want hear about the butterfly in general.
Ahahaha I actually donate things one by one to hear cool facts about them. Also because I love blathers but I genuinely want to learn about the items I’m donating.
Most of the time, I choose to skip. I usually don't care that much about bug / fish facts, especially since they're too long. I usually mash through the dialogue in the event I accidentally choose to tell Blathers to tell me more about a given donation.
I'm the same as you, if I'm just donating one thing and it's not a bug, I listen 'cause I feel bad otherwise
I saw a version of the "woman yelling at cat w/ salad meme" that was like:
Woman: VIDEO GAMES CAUSE VIOLENCE
Cat: Me, listening to Blathers ramble so I don't hurt his feelings
i’ve gotten into the habit of donating in bulk so i haven’t had blathers tell me any facts in a while but before, i always used to listen as i felt bad for skipping through considering he’s one of my favourite npcs and i like what he has to say ^~^