No way of knowing without input from what they're seeing there. If they're sitting in their car in a residential neighborhood (not their own), the only "open" connections they see may be ad-hoc connections, with the rest being WEP or WPA secured, internet-enabled wifi connections.

Certainly, at their own house, they should be able to see their own wifi AP and be able to connect normally, but without getting a more complete story from the original poster, it's hard to diagnose.