Why do real estate agents drive buyers around to show houses for sale when they aren t representing them?

I am studying for my exam right now, and I know that an agent who represents a seller, often drives buyers around to help them look for houses. Apparently this confuses the buyers often, believing that the agent is representing them when they aren't… So I'm confused.

Read more: Why do real estate agents drive buyers around to show houses for sale when they aren t representing them?