You are identifiying junk mail. Why don't you block them?
You are getting emails marked as Junk, but you are wondering why they are not just blocked?
The issue of False Positives
You can log into webmail or manage.shaw.ca and choose to have them deleted immediately if you wish for your account.
Personally, I have mine set to Tag and Deliver, so I can see what Shaw marks as junk, incase I need to troubleshoot a mail issue.
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