Damn right. We do the same here and regularly ride around scanning for unauthorized APs, which really means ANY APs. Also, if the MAC address isn't registered then it's NOT going anywhere on the network. It would be best if you approached your IT folks with the idea of a secured wi-fi network utilizing WPA2 and RADIUS combined with MAC address filtering beyond the AP at the switch/router. If they babble about how unsecure wi-fi is, then they're *****s.