CASL is a bad law and cannot reasonably be justified on any basis. On that issue, I recommend you read a feature article in the Financial Post today The great anti-spam cash grab. Here are a few choice extracts from the article.
…CASL is a bad law. It offers no benefit to consumers, yet imposes red tape and additional costs on businesses. Worse still, it reduces competition, actually harming consumers. Finally, it is inconsistent with Canada’s free market economy and very likely unconstitutional…
CASL cannot work.