As a matter of fact it HAS HAPPENED. A couple of businesses who were being, shall we say, economic with the truth in customs forms, got their parcels sent back by the CBSA along with a cease and desist or else letter. Some members here remember that crackdown because they had parcels that never made it to them and had to sort it out with the vendors.I am not concerned about this. There have been hundreds of posts asking this same question and receiving similar answers over the past decade across various forums, FB, reddit, etc., and it hasn't amounted to any noticeable crackdown. Any competent or driven agent would be able to use a simple Google search to quickly come up with a list of companies to flag. This has not happened.
If the Gov't really wanted to act, they'd be tagging every SP package that crossed the border. As it is, this doesn't happen. In all my experience, I got tagged half the time (I have terrible luck). My buddy has ordered nearly monthly for a few years from them, and only gets hit about 10% of the time. I mean, SP is very clear what they are sending and it is in the name, yet they aren't persecuted extensively.
If the PTB doesn't tag every SPC package is because SPC has been fully declaring the contents (they were not one of those couple of businesses referred to in the previous paragraph), a reason why they aren't being persecuted.