They can help strengthen a point as long as the question is then enforced. They help to convince the listener since usually even thought it's not said we usually think yes in our head after hearing a rhetorical question.
Since an argumentative speech is an influential discourse in which the presenter tries to convince his audience to change their standpoints on a provocative subject. So rewriting this will give us this kind of speech: "Do you play sports? Have you ever given soccer, cricket, or field hockey a try? You might be surprised to learn that are the world's popular sports. Statistically speaking, they are more popular than typical American sports such as baseball and basketball.
