You're right mate. Main use was for Banana Weevils. Another cheap source of Fipronil is from some of the dog and cat flea treatments.
If you ever want a really good ant bait get your mitts on some Regent 200SC and mix 5ml in 400g of Honey (or 1g of active depending on what product you use). One drop will wipe out a whole nest. If the ants you're chasing won't eat sweet stuff then mix 5ml in 400g of minced meat. These mixes will take every ant species I've ever tried it on and will knock out nests overnight. I've had 200 acre growers wipe out basically every ant on their citrus property with half a jar.
It took us years to get this mix right to avoid bowling them over before they got back to the nest.
It is absolutely amazing but completely off label of course