It shouldn't be a taxable benefit in my mind, as it most certainly is taken out "wholly, exclusively and necessarily" for the purpose of the job.
We should all get a judicial review on the matter as the IR won't concede unless forced (the money-grabbing, unhelpful, idiots).
Little story - do you know why parking spaces at work are NOT taxed as a Benefit in Kind?
Because the Revenue bosses raised such a fuss when proposed, since they have such a privilege themselves.
Answer: get friendly with a taxman, and get him hooked on aviation.