Vantage River Cruise Contest - Curious about THIS

I entered the drawing for their free cruise. Looked interesting. But I found this in the rules:

"7. Requirements of Potential Winner. Except where prohibited, the potential Grand Prize Winner must complete and return an affidavit of eligibility and liability/publicity release (the “Affidavit/Release”) within ten (10) days of being notified. If a potential winner is a resident of Canada, he/she will also be required to correctly answer a time-limited skill testing question without any assistance in order to receive the prize."

Why are Canadians subjected to this? So, if they win the drawing, and let's say they FAIL to answer the question - does that mean they're disqualified and it's passed to someone else? This doesn't seem fair, does it?

Would you consider posting this to the River Cruising board? Readers there may be familiar with Vantage River Cruises and have some suggestions to offer.