You and just about everyone else does. If you have a decent connection you will pull host just about every time. Just don't be like 70% of the other users and try to manipulate your connection to avoid being host, it just makes matters worse for everyone.

If you can get into your router settings switch off upnp, this does not mess up other peoples games but it will stop you from getting host all the time. You will still get the odd game as host but nowhere near as often.