Was probably a partner of google advertising on Google's behalf. ex. "Sign up with us to get a free google adwords voucher!"
Even if it was Google doing the advertising it doesn't hurt to advertise in multiple places using different means.
If you had a choice between advertising on TV or Radio or both and you had a pretty much limitless budget, which would you choose? I sure as hell wouldn't stick to just one!
Image is too small to even make out what the ad sais...