I agree with PMG, theo, etc. When you are given tickets by your employer, there is an expectation you will use them, or will give them (in some cases) to friends/clients/etc to promote goodwill for your company.
Forgetting corporations, if a relative or friend gave me tix, and instead of going I sold them for profit, I guarantee they wouldn't give me tix again and would prob be pretty miffed.
Its wrong no matter how you color it. This dude is getting his just desserts.