Fly 320s might be able to tell us if this is something the FAA would get involved with and pursue from the criminal side for the safety violations.
Violating the Federal Aviation Regulations isn't normally a criminal act. Considering the press over the maintenance brouhaha with Southwest and American these last few months, then yes, I can see the FAA getting involved. The end result would probably be that the Captain and any involved flight attendants would be fired, but I doubt that the FAA would take action beyond that. That is, of course, if the accusation is true.
Requiring a customer to occupy a lav seat, is certainly a violation, though. If the story is true, I expect people to be fired.
Buddy pass fees vary at each airline. Some don't charge a fee, some charge applicable taxes, some have a flat rate. At every airline I've worked, buddy passes could not be sold or bartered. Lately, the IRS has decided that buddy passes and other similar benefits are taxable, therefore the employee that gives the buddy pass has to pay tax on that pass.
Yes, non-revenue passengers are scum-of-the-earth.
They are the last ones to get a seat and the first ones to get kicked-off. I've been kicked-off, politely, numerous times.
IIRC, Jetblue has several (4?) extra cabin jumpseats that can be used by qualified personnel.