Growing up we had an old aluminum canoe. It looked kind of ugly, and had some dents, but it was a great boat. Over the past 5 years I've been in various sporting goods stores in California, Colorado, and Idaho looking at canoes. Every single canoe they have on display is plastic. They never have aluminum canoes. Aluminum canoes that I've found on the internet are price competitive (generally slightly cheaper), and weigh less than the plastic canoes. 

My own biased perception is the aluminum canoes are more durable, hardier (in and out of the water since they can't warp if stored in the sun), require less maintenance, and if they are damaged are easier to fix. I know that I'm biased so I don't understand why the market seems to be dominated by plastic canoes. What am I missing? Why are plastic canoes everywhere and aluminum canoes hard to find? Is there something in the pro/con list between the respective build materials that makes plastic canoes a clear winner?