Playing devil’s advocate here: the message itself could be written in an easily legible font (plus an image, potentially), and the company logo could still be cursive or whatever, making it much more distinct. Once the logo shape is learned, it should be easy to recognize.
Many logos use cursive or letters which one must "focus" in order to read.
But if you use a "simple font" you asap read it without even knowing.
If you want to get the most out of your ads you need the people to actually register the ad message instantly.