Today's convoluted explanation of why something isn't spam is provided by rasimport.com.br. Here's a (somewhat free) translation from the Portuguese disclaimer at the end of their messages:
Important Message: Our message is not spam, here's why: email is a form of correspondence equal to a telephone connection or a letter. In Brazil and in the rest of the world, in the same way that no authorization is necessary to send letters or to telephone somebody, it is likewise unnecessary [to have] prior authorization to send emails in whatever form, there is nothing in Brazilian legislation that refers to the practice of spam, ...
At this point the Portuguese becomes quite opaque (so much so that I wonder if it's not their grammar rather than my very limited grasp of Portuguese that's at fault) but they appear to be arguing that in any case, should such a regulation exist, it will be restricted to requiring that the sender provide an opt-out mechanism.
I'm sure you'll all agree that this is a fascinating argument. I look forward with great eagerness to hearing their justification of why they should be allowed to forge my email address in the 'From:' line of the spams that they send out.