As revealed by the comic, Paint the Town, Yordles are (according to Heimerdinger) feared, hunted, and eliminated by humans all across Runeterra.
As of the events of said comic, Jinx and Ziggs blew up the Warden station in Piltover (wardens are basically the police of Piltover), and were both placed under arrest.
However, rather than appearing as a simple human due to his Yordle Glamour, the people managed to see him for what he truly is, a Yordle.
Jinx was already a wanted criminal in Piltover for a long time, but now, a Yordle, otherwise thought to just be a myth, has been identified as a threat by the Piltover Wardens.
This intrigued me, as one of Caitlyn's abilities, her W, named "Yordle Snap Trap", is seemingly a trap designed to catch Yordles.
I always found it strange why someone tasked with catching criminals would use bear traps in their line of work, much less use *cupcakes* as bait.
And this made me think that Caitlyn might be hunting Yordles, and there's a lot of support for it too.
First of all, the main thing about the Y.S.T is that it uses a cupcake as bait, and Ziggs was shown both eating cakes after blowing up Aleco's Sweetcakes store, as well as having "Devil Jinx" on his shoulder try to convince him to blow up the warden station by promising him cakes for it, indicating that Ziggs (and possibly all Yordles) have a love for cakes or just sweet things in general.
Second of all, if you play as a Yordle champion against Caitlyn Bot in Co-op vs. AI, Caitlyn Bot says this: *"I've got a Yordle Snap Trap cupcake for you, little Yordle."*, also implying that Caitlyn hunts Yordles.
(Yes, I know I'm using a bot quote as evidence, but bot quotes should be considered just as canon as any other voiceline the champion has).
It may very well be that after the events of Paint the Town, the Piltover Wardens called for a mass hunting and extermination of Yordles, not unlike pest control in our world, and Caitlyn saw fit to help due to her skills as a hunter during her earlier years.
Other than the bear traps with cupcakes for bait, I also found it odd that Caitlyn carries all these nets around, but it makes a lot more sense if she's also tasked with catching "vermin" on the side.
Either way, just something interesting I thought about today.