For bedding, for their nest, mine really like using shredded paper.
Just my opinion, I do not know for sure, but I think the shredded paper helps them keep the warmth better and also absorbs the smell.
My wife shreds all the paper copies of our bills and such, so I always have a good supply. But really, I do not have to change their actual bedding much.

As for treats, mine , well some of mine love and I mean LOVE peanut butter. At 1st I started giving them some from the end of a zip tie. Now, most will eat it right off my finger.
I stole some of my wife's Cheeto before and they do like those as well.
I also give them pieces of my pizza crust, the really seem to like that as well.