In the sport of skiing there is a very grey area between Pro and Am. Unlike other sports we don't have teams, drafts, or a Tour.
The closest to our sport would be Golf, considering everyone is an independent contractor and you must win to make money doing it.
Salaries from companies to ski for them are more like endorsements and not working salaries like basketball players.
From what I have said above I believe you should be called a 'pro' when you compete in the 'pro' competitions like the X-games WSI and others.