It's not at all useless: it enables the application to bypass limitations in Python, i.e. process the sockaddr on its own (very much in the same way as you have to do for ioctl/fcntl).

Whether it's surprising or not depends on what you expected to happen. Python always tries to expose system interfaces unmodified, so one "should" expect something like this to happen when there is a real chance that the system returns data which Python cannot interpret.

What is puzzling is that you (reportedly) get a TypeError when you pass them to the socket creation (or connect); instead, it should tell you that the address family is not supported.