not the image I expected

A company, which shall remain nameless, advertises frequently on TV that they can help students with focus or other issues to improve their grades and do better in school.  I envisioned, based on the ads, this company being run by bright professionals who really knew what they were doing.  Imagine my surprise then to find a letter from this company in my mailbox, in an envelope with no address and no stamp. The last I knew this is totally illegal.  Shouldn't a company who educates people know this?