" Couple this with the fact that the Parks Canada strongly discourages forest camping and specifies that tents and sleeping be done on the beaches."

I haven't camped on this trail, but have in the WA Olympics where most beaches are close to the surf and the water full of logs that can be tossed all the way up the beach. Are the beaches not hazardous for sneaker waves and caber tossing?

I can see why it would be more Leave No Trace to camp on a beach.

Here is some more reading.

http://backpackinglight.com/search/?q=west+coast+trail