I understand why they're not catchable since they only show up if you dont play the game for a long time, and encouraging that is bad game design.Even though these aren’t catchable bugs, my favorite are the roaches.
I maintain my rooms with roaches, and also add those toy ones here and there.
You could catch roaches on flowers in older Animal Crossing games, as I recall. Not sure why they removed them in later games.they really feel like they should be catchable