I love many silent comedies, with their pratfalls and stunts mixed with real human bathos, but this Harold Lloyd "comedy" consists of an hour+ of sight gags involving pain and violence. The only thing that distinguishes this film is the presence of the "giant," who is there to wreak havoc (in a "good" way) and provide a grotesquerie rather than a truly sympathetic character.
Some would say that the pain and debasement of others is the root of most physical humor, and that's still in evidence today (look at "Home Alone" and many other adolescent-minded comedies.) I personally think comedy can be kinder, gentler, and much funnier.
Why Worry? glorifies war and violence and the pain-gags get old very quickly...