What the company (Fairmont, in Banff) is telling you is that they will not sponsor someone to come to Canada to work. You must already be eligible to legally work in Canada to apply (or more precisely, be accepted).
If you are not a Canadian citizen or permanent resident ... or do not already have a work visa (which is usually tied to a specific employer), then you are not legally eligible for work in Canada.
This same criteria holds true if someone from outside the US wanted to legally work in the US, by the way.
The most common method of obtaining a work visa is to qualify as a skilled worker (which means advanced academic degree, several years' relevant experience, or both) and being offered a position by a company that advertises internationally (i.e. in a national newspaper that is NOT from the country where the employer is located).
It *is* possible to obtain a temporary work visa ... but it's much harder to do. Basically, the employer states that "I have a need for X number of employees RIGHT NOW, and there aren't enough in teh immediate area to accomplish what needs to be done". Then the employer goes through the paperwork required to sponsor foreigners to work on a temporary basis.