Fried wontons are different from wontons in soup, apart from the fact that they're fried.
The filling for boiled wontons should have dried sole (大地鱼, aka 铁脯). The fish is toasted till brown, crisp and fragrant, then chopped into little bits.
With either of these ingredients in the filling, wontons cooked in soup would have a rich, intense aroma they wouldn't have otherwise. In Hong Kong, the