Switching from Wages to Commission - Legal?

Hi,
My work is thinking about switching some of us (I work at a Triple-A baseball club) hawkers to commission instead of our $6.85 CDN minimum wage. I believe that on slow or most nights depending on percentage, this will make our work pay less then minimum wage would. Any ideas if this is legal, or any thoughts? (I know this forum isn’t IMHO, but the question is of more importance to me).

Thanks!