Crown Royal, Canadian Club, and Seagram's 7 are Canadian Rye whiskeys, no corn, so not bourbon. The secondary grain in these is wheat. They are blended whiskeys, because they are composed of whiskeys of different batches and vintages, to produce a consistent flavour, like blended Scotch whiskys. Single-malt whiskeys are the spirit equivalent to vintage wines, single year, no blending, so the flavour changes from year to year. I have run across this with my favourite single-malt, the aforementioned Lagavulin. Is there an analgous term for bourbons, pot something?
There are some newly-released single-malt Canadian rye whiskeys, which I have not yet tried, but hope to, soon.