Your substrate may be too firm. It may be too much work for them to bury themselves every day, so they figure "screw it". Even my tadpole raised toads bury themselves every day. I keep them in pretty loose "Yard Dirt" (see my post on keeping Am's)with a few large dead leaves and pieces of bark. They usually don't bury themselves completely, they are usually half buried under a leaf or bark. Most of the time I see them peering out from beneath the shelter, like they are waiting to ambush something. They seem pretty happy this way. Even the wild ones in the infirmary tank will greet me as I walk in the room by approaching the glass at feeding time after only a few days. They like to have something they can crawl under and at least make a shallow pallet to sleep in. I've seen some of them use the same pallet every day without digging as long as it was deep enough,fit their bodies close enough, and had a low enough piece of cover. One of my toads backs herself into the same depression, under the same piece of bark every day. She seems to do this very carefully so she doesn't disturb the size and shape of the hole. When I change her "yard dirt", I always put the bark back in the same place and the first thing she does when I put her back in her home is re-excavate her little house, exactly the way it was before.
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How to get your wife to like toads; 1.Get a male toad. 2.Get him to hug your wifes wrist (amplexus). 3. Tickle him so he chirps in protest. 4.Say "Awww, he likes you". Note; Make sure he pees first or you may receive bodily harm during this procedure.