It is possible, at least with some smartphone (and some, new) adroid releases to have a smartphone connected to a wi-fi network and to use it for usb tethering (of course not for wi-fi hotspot).
This could sound a bit strange, but it can be useful, i,g., if your laptop has not a wi-fi reception as powerful as your smartphone: so, you can use your smartphone to receive the wi-fi signal and to share it with the laptop.