Italian chocolate is of a very high standard. Your previous post said you were in Italy in October, and the annual European chocolate fair in Perugia is from 16 - 25 October, about 90 minutes south of Florence if you want to visit somewhere a bit different. I suspect Hersheys perhaps doesn't compete.
If you can transport it, one thing that is surprisingly expensive in Italy is non-italian wine, especially US and Australian wine, so if your hosts tastes include alcohol a decent bottle would go down well - just expect your hosts to be well informed about grape varieties, growing conditions, the effects of local climate, etc. While there's plenty of local wine in supermarkets here for €3 a bottle or less, there' s a surprising amount of italian wine at € 30 +, so it needs to be good to impress!