Yeah, because we all know how much "hacking" is required to use wide open WiFi connections.
Yeah. Technically you are allowed to connect to any fully open network. The wireless AP has an option to ignore the request to associate if it likes or request it be encrypted, and it didn't. Therefore, you should be allowed to connect to any network using this prinicpal. If the guy bypassed the MAC filtering or WEP to get in, it'd be a different story.