A true "Summer Tire" is not just a tire that is not a Winter Tire, but a special design for high traction on dry surfaces, but not good in rain or snow. Very few people, even in the southern parts of the US, use Summer Tires. They typically use All-Season Tires, because they are also useful in heavy rain, not just snow.
I would be very surprised if Canada will pass a law that mandates the use of "true" Summer Tires. If you look at the tire rack listing you provided, the only Hankook tires in the list were Summer Tires. Not sure which exact Hankook tires come with the US or Canadian Genesis models.
This is a common misconception that summer tires are not good in the rain. Here's an article from Tire Rack mentioning that summer tires, not all-season ones, are best for rainy conditions:
Best Tires for Rain
Monday, June 18, 2012 by Ben Rooney
Traveling in the rain can be a nerve-wracking experience without the right tires. A tire with superior wet weather traction can be a big safety benefit for drivers who need to travel at speed in wet conditions.
I often hear customers say, "It rains a lot where I live, so I need to have an all-season tire." While the name all-season implies that a tire might be the best tire for every season, the reality is that the compound and tread pattern of an all-season tire is actually a compromise between wet, dry and snow capability. Each of these conditions have different requirements, so an all-season tire actually gives away some wet and dry traction to gain light snow traction.
Summer tires are the ultimate wet weather performers. They have sticky compounds to grip wet pavement and tread patterns designed to let water flow through and away from the contact patch. The current class leaders in wet and overall traction are the Michelin Pilot Super Sport and Bridgestone Potenza S-04.
Two general notes about wet traction apply to pretty much any set of tires: Tread depth is essential to good wet weather performance. We have an entire tech article dedicated to illustrating how important adequate tread depth is when encountering wet conditions. Second, tire inflation is also a vital component to proper tire performance in wet weather and you can find in depth information as well as the meaning behind the image at the top left by reading "Air Pressure vs. Wet Performance."
If you live in a warm climate and need the best wet traction, definitely consider a summer tire. Regardless of where you are or what type of tire you have, if rain is in the forecast make sure that your tread depth and tire inflation are up to spec.
http://blog.tirerack.com/blog/bens-blog/best-tires-for-rain
At the end of the day it is not more expensive as wear is divided between the 2 sets, just makes the roads safer in general IMHO.
