I don't agree that an industry wide ban should be at the discretion of a single airline.
If that penalty is incorporated into the law of the land and imposed by the courts, fine - but not at the decision of one company.
From Jet2's terms and conditions:
23. Conduct on Board Aircraft and at Airport and Safety
23.1
You must behave appropriately at all times whilst in the airport and on board the aircraft. In particular (but not limited to these examples) you must not:
- contravene any applicable law (e.g. by being drunk on board an aircraft);
- conduct yourself aboard the aircraft so as to endanger the aircraft or any person or property on board;
- obstruct the crew in the performance of their duties;
- fail to comply with any instruction of the crew;
- use any threatening, abusive or insulting words or actions towards the crew or other passengers;
- behave in a disorderly manner or in a manner to which other Passengers may reasonably object;
- fail to comply with the terms of any document signed by you following contravention of one or more of the preceding conditions on a previous flight with us.
23.2
If, in our reasonable opinion, you have failed to behave appropriately either in the airport or on board the aircraft or we consider you unfit to fly:
- you may be prosecuted for offences committed on board the aircraft;
- we may decide (in our reasonable discretion) to cancel your flight prior to take-off and/or, after take-off;
- divert the aircraft to offload you, in which case you must pay to us all costs and expenses which we incur of any nature whatsoever as a result of or arising out of that diversion;
- we may decide to cancel any return flight or other future flights you have with us, without refund;
- we may take any other measures we deem necessary to prevent continuation of your inappropriate conduct, including your restraint or removal from the aircraft or airport.
In all of the above circumstances, you shall not be refunded the price of your booking, and we shall not be liable for any costs you incur as a result of us refusing carriage.
You will indemnify us for all costs and expenses (including the legal costs we incur in bringing any action against you) arising from your improper conduct on board the aircraft including (but not limited to) any damage caused to the aircraft.
23.3
We reserve the right to request that you undertake a breath test procedure at any time prior to travel. If you either refuse to take the test or fail the test, we reserve the right to refuse you permission to travel. Notwithstanding this right, even if you pass the test we still remain entitled to act in accordance with clause 23.2 in our absolute discretion.
Not sure if these specific T&Cs have been tested in court but (IMHO) appear to be imbalanced (i.e. they have all the protection, the customer has little) and deny any possibility of appeal. They also appear to be poorly written (for example the title is not good English - and 'Safety' is only inferred. They also (appear to) fail to reserve the right to offload the passenger before departure - only to cancel the flight. Sloppy.
I'd say the refusal to refund unused future tickets is not a 'fair term' and could come back to bite them. Having decided to unilaterally cancel their contract(s), without appeal, they should refund the 'price of your booking' (whatever that is)
Don't get me wrong, I'm not saying that in this specific case they are acting inappropriately but contract terms (particularly those that one party has no ability to modify) cannot be unbalanced. These appear to be exactly that. They need to find a good lawyer to redraft this for them, in terms with UK law.