Compared to Bowers or Johansen, who is a family known for lynching black people, and a family known for committing atrocious acts of imperialism, Hitler is a much better name. I'd never want my kids to have last names such as Bower, Tupper, Johnasen -- much more evil last names.
There are certain words that conjure up different emotions based on their history and Hitler is one of them. Had Hitler been a first name this could be a different story but it is a last name so it would be even more usual for that name to be picked. It just shows hate and ignorance on the parents' part.