> the term “exceeds authorized access” means to access a computer with authorization and to use such access to obtain or alter information in the computer that the accesser is not entitled so to obtain or alter;
The information they were accessing didn't come from the computer. And this doesn't say anything about using a computer service in an unauthorized way, which is what it sounds like you're describing here
The output buffer on the Internet side of the router is information in the computer. It was modified without authorization when packets were sent through it.
Not really. If the plane has open Wlan or a well-known password (ie in the info stuff) then all you need to is connect. No further authorization needed. There is simply no need to open a browser.
These sorts of technicalities don't play well with juries, but neither do large airlines or ~phone companies charging $15 for two hours of 1Mbps internet.