On the one hand, they posted it in the clear on their website.
On the other, clearly it's meant for the pilots.
On the first hand again, if the code doesn't cost the organization anything per user, just the hotel, does it harm the organization?
On the other hand, if they did kick in something to get that discount, that would harm them.
Back to the first hand, if the hotel is willing to rent that room on the same day for half the cost, why pay the full price?
On the other hand, it would be dishonest to misrepresent oneself. (And what happens if they later want proof that you qualify?)
What would you do?
And is it cheaper to book by phone? By Web? By third party site?