Charge? 9.95 for the WiFi
? Even McDonalds gave that practice up
So share (Literally) the 'registered' laptop .
Bridge the Wifi to the LAN port and BYO wired switch+cables (or a Wifi router) to serve the others. (Shared Network connection, like they used to do when people used dialup in a house with more than 1 computer)
It will take some fiddling and assigning a Static IP to the LAN Port and WAN side of the router.